LCOV - code coverage report
Current view: top level - src/backend/executor - nodeIndexscan.c (source / functions) Hit Total Coverage
Test: PostgreSQL 17devel Lines: 480 537 89.4 %
Date: 2024-04-25 00:11:39 Functions: 22 22 100.0 %
Legend: Lines: hit not hit

          Line data    Source code
       1             : /*-------------------------------------------------------------------------
       2             :  *
       3             :  * nodeIndexscan.c
       4             :  *    Routines to support indexed scans of relations
       5             :  *
       6             :  * Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group
       7             :  * Portions Copyright (c) 1994, Regents of the University of California
       8             :  *
       9             :  *
      10             :  * IDENTIFICATION
      11             :  *    src/backend/executor/nodeIndexscan.c
      12             :  *
      13             :  *-------------------------------------------------------------------------
      14             :  */
      15             : /*
      16             :  * INTERFACE ROUTINES
      17             :  *      ExecIndexScan           scans a relation using an index
      18             :  *      IndexNext               retrieve next tuple using index
      19             :  *      IndexNextWithReorder    same, but recheck ORDER BY expressions
      20             :  *      ExecInitIndexScan       creates and initializes state info.
      21             :  *      ExecReScanIndexScan     rescans the indexed relation.
      22             :  *      ExecEndIndexScan        releases all storage.
      23             :  *      ExecIndexMarkPos        marks scan position.
      24             :  *      ExecIndexRestrPos       restores scan position.
      25             :  *      ExecIndexScanEstimate   estimates DSM space needed for parallel index scan
      26             :  *      ExecIndexScanInitializeDSM initialize DSM for parallel indexscan
      27             :  *      ExecIndexScanReInitializeDSM reinitialize DSM for fresh scan
      28             :  *      ExecIndexScanInitializeWorker attach to DSM info in parallel worker
      29             :  */
      30             : #include "postgres.h"
      31             : 
      32             : #include "access/nbtree.h"
      33             : #include "access/relscan.h"
      34             : #include "access/tableam.h"
      35             : #include "catalog/pg_am.h"
      36             : #include "executor/executor.h"
      37             : #include "executor/nodeIndexscan.h"
      38             : #include "lib/pairingheap.h"
      39             : #include "miscadmin.h"
      40             : #include "nodes/nodeFuncs.h"
      41             : #include "utils/array.h"
      42             : #include "utils/datum.h"
      43             : #include "utils/lsyscache.h"
      44             : #include "utils/rel.h"
      45             : 
      46             : /*
      47             :  * When an ordering operator is used, tuples fetched from the index that
      48             :  * need to be reordered are queued in a pairing heap, as ReorderTuples.
      49             :  */
      50             : typedef struct
      51             : {
      52             :     pairingheap_node ph_node;
      53             :     HeapTuple   htup;
      54             :     Datum      *orderbyvals;
      55             :     bool       *orderbynulls;
      56             : } ReorderTuple;
      57             : 
      58             : static TupleTableSlot *IndexNext(IndexScanState *node);
      59             : static TupleTableSlot *IndexNextWithReorder(IndexScanState *node);
      60             : static void EvalOrderByExpressions(IndexScanState *node, ExprContext *econtext);
      61             : static bool IndexRecheck(IndexScanState *node, TupleTableSlot *slot);
      62             : static int  cmp_orderbyvals(const Datum *adist, const bool *anulls,
      63             :                             const Datum *bdist, const bool *bnulls,
      64             :                             IndexScanState *node);
      65             : static int  reorderqueue_cmp(const pairingheap_node *a,
      66             :                              const pairingheap_node *b, void *arg);
      67             : static void reorderqueue_push(IndexScanState *node, TupleTableSlot *slot,
      68             :                               Datum *orderbyvals, bool *orderbynulls);
      69             : static HeapTuple reorderqueue_pop(IndexScanState *node);
      70             : 
      71             : 
      72             : /* ----------------------------------------------------------------
      73             :  *      IndexNext
      74             :  *
      75             :  *      Retrieve a tuple from the IndexScan node's currentRelation
      76             :  *      using the index specified in the IndexScanState information.
      77             :  * ----------------------------------------------------------------
      78             :  */
      79             : static TupleTableSlot *
      80     1903272 : IndexNext(IndexScanState *node)
      81             : {
      82             :     EState     *estate;
      83             :     ExprContext *econtext;
      84             :     ScanDirection direction;
      85             :     IndexScanDesc scandesc;
      86             :     TupleTableSlot *slot;
      87             : 
      88             :     /*
      89             :      * extract necessary information from index scan node
      90             :      */
      91     1903272 :     estate = node->ss.ps.state;
      92             : 
      93             :     /*
      94             :      * Determine which direction to scan the index in based on the plan's scan
      95             :      * direction and the current direction of execution.
      96             :      */
      97     1903272 :     direction = ScanDirectionCombine(estate->es_direction,
      98             :                                      ((IndexScan *) node->ss.ps.plan)->indexorderdir);
      99     1903272 :     scandesc = node->iss_ScanDesc;
     100     1903272 :     econtext = node->ss.ps.ps_ExprContext;
     101     1903272 :     slot = node->ss.ss_ScanTupleSlot;
     102             : 
     103     1903272 :     if (scandesc == NULL)
     104             :     {
     105             :         /*
     106             :          * We reach here if the index scan is not parallel, or if we're
     107             :          * serially executing an index scan that was planned to be parallel.
     108             :          */
     109      117590 :         scandesc = index_beginscan(node->ss.ss_currentRelation,
     110             :                                    node->iss_RelationDesc,
     111             :                                    estate->es_snapshot,
     112             :                                    node->iss_NumScanKeys,
     113             :                                    node->iss_NumOrderByKeys);
     114             : 
     115      117590 :         node->iss_ScanDesc = scandesc;
     116             : 
     117             :         /*
     118             :          * If no run-time keys to calculate or they are ready, go ahead and
     119             :          * pass the scankeys to the index AM.
     120             :          */
     121      117590 :         if (node->iss_NumRuntimeKeys == 0 || node->iss_RuntimeKeysReady)
     122      117590 :             index_rescan(scandesc,
     123      117590 :                          node->iss_ScanKeys, node->iss_NumScanKeys,
     124      117590 :                          node->iss_OrderByKeys, node->iss_NumOrderByKeys);
     125             :     }
     126             : 
     127             :     /*
     128             :      * ok, now that we have what we need, fetch the next tuple.
     129             :      */
     130     1906054 :     while (index_getnext_slot(scandesc, direction, slot))
     131             :     {
     132     1504650 :         CHECK_FOR_INTERRUPTS();
     133             : 
     134             :         /*
     135             :          * If the index was lossy, we have to recheck the index quals using
     136             :          * the fetched tuple.
     137             :          */
     138     1504650 :         if (scandesc->xs_recheck)
     139             :         {
     140      325858 :             econtext->ecxt_scantuple = slot;
     141      325858 :             if (!ExecQualAndReset(node->indexqualorig, econtext))
     142             :             {
     143             :                 /* Fails recheck, so drop it and loop back for another */
     144        2782 :                 InstrCountFiltered2(node, 1);
     145        2782 :                 continue;
     146             :             }
     147             :         }
     148             : 
     149     1501868 :         return slot;
     150             :     }
     151             : 
     152             :     /*
     153             :      * if we get here it means the index scan failed so we are at the end of
     154             :      * the scan..
     155             :      */
     156      401400 :     node->iss_ReachedEnd = true;
     157      401400 :     return ExecClearTuple(slot);
     158             : }
     159             : 
     160             : /* ----------------------------------------------------------------
     161             :  *      IndexNextWithReorder
     162             :  *
     163             :  *      Like IndexNext, but this version can also re-check ORDER BY
     164             :  *      expressions, and reorder the tuples as necessary.
     165             :  * ----------------------------------------------------------------
     166             :  */
     167             : static TupleTableSlot *
     168       82662 : IndexNextWithReorder(IndexScanState *node)
     169             : {
     170             :     EState     *estate;
     171             :     ExprContext *econtext;
     172             :     IndexScanDesc scandesc;
     173             :     TupleTableSlot *slot;
     174       82662 :     ReorderTuple *topmost = NULL;
     175             :     bool        was_exact;
     176             :     Datum      *lastfetched_vals;
     177             :     bool       *lastfetched_nulls;
     178             :     int         cmp;
     179             : 
     180       82662 :     estate = node->ss.ps.state;
     181             : 
     182             :     /*
     183             :      * Only forward scan is supported with reordering.  Note: we can get away
     184             :      * with just Asserting here because the system will not try to run the
     185             :      * plan backwards if ExecSupportsBackwardScan() says it won't work.
     186             :      * Currently, that is guaranteed because no index AMs support both
     187             :      * amcanorderbyop and amcanbackward; if any ever do,
     188             :      * ExecSupportsBackwardScan() will need to consider indexorderbys
     189             :      * explicitly.
     190             :      */
     191             :     Assert(!ScanDirectionIsBackward(((IndexScan *) node->ss.ps.plan)->indexorderdir));
     192             :     Assert(ScanDirectionIsForward(estate->es_direction));
     193             : 
     194       82662 :     scandesc = node->iss_ScanDesc;
     195       82662 :     econtext = node->ss.ps.ps_ExprContext;
     196       82662 :     slot = node->ss.ss_ScanTupleSlot;
     197             : 
     198       82662 :     if (scandesc == NULL)
     199             :     {
     200             :         /*
     201             :          * We reach here if the index scan is not parallel, or if we're
     202             :          * serially executing an index scan that was planned to be parallel.
     203             :          */
     204          46 :         scandesc = index_beginscan(node->ss.ss_currentRelation,
     205             :                                    node->iss_RelationDesc,
     206             :                                    estate->es_snapshot,
     207             :                                    node->iss_NumScanKeys,
     208             :                                    node->iss_NumOrderByKeys);
     209             : 
     210          46 :         node->iss_ScanDesc = scandesc;
     211             : 
     212             :         /*
     213             :          * If no run-time keys to calculate or they are ready, go ahead and
     214             :          * pass the scankeys to the index AM.
     215             :          */
     216          46 :         if (node->iss_NumRuntimeKeys == 0 || node->iss_RuntimeKeysReady)
     217          46 :             index_rescan(scandesc,
     218          46 :                          node->iss_ScanKeys, node->iss_NumScanKeys,
     219          46 :                          node->iss_OrderByKeys, node->iss_NumOrderByKeys);
     220             :     }
     221             : 
     222             :     for (;;)
     223             :     {
     224       87856 :         CHECK_FOR_INTERRUPTS();
     225             : 
     226             :         /*
     227             :          * Check the reorder queue first.  If the topmost tuple in the queue
     228             :          * has an ORDER BY value smaller than (or equal to) the value last
     229             :          * returned by the index, we can return it now.
     230             :          */
     231       87856 :         if (!pairingheap_is_empty(node->iss_ReorderQueue))
     232             :         {
     233       10250 :             topmost = (ReorderTuple *) pairingheap_first(node->iss_ReorderQueue);
     234             : 
     235       20494 :             if (node->iss_ReachedEnd ||
     236       10244 :                 cmp_orderbyvals(topmost->orderbyvals,
     237       10244 :                                 topmost->orderbynulls,
     238       10244 :                                 scandesc->xs_orderbyvals,
     239       10244 :                                 scandesc->xs_orderbynulls,
     240             :                                 node) <= 0)
     241             :             {
     242             :                 HeapTuple   tuple;
     243             : 
     244        5076 :                 tuple = reorderqueue_pop(node);
     245             : 
     246             :                 /* Pass 'true', as the tuple in the queue is a palloc'd copy */
     247        5076 :                 ExecForceStoreHeapTuple(tuple, slot, true);
     248        5076 :                 return slot;
     249             :             }
     250             :         }
     251       77606 :         else if (node->iss_ReachedEnd)
     252             :         {
     253             :             /* Queue is empty, and no more tuples from index.  We're done. */
     254          18 :             return ExecClearTuple(slot);
     255             :         }
     256             : 
     257             :         /*
     258             :          * Fetch next tuple from the index.
     259             :          */
     260       82762 : next_indextuple:
     261       86902 :         if (!index_getnext_slot(scandesc, ForwardScanDirection, slot))
     262             :         {
     263             :             /*
     264             :              * No more tuples from the index.  But we still need to drain any
     265             :              * remaining tuples from the queue before we're done.
     266             :              */
     267          18 :             node->iss_ReachedEnd = true;
     268          18 :             continue;
     269             :         }
     270             : 
     271             :         /*
     272             :          * If the index was lossy, we have to recheck the index quals and
     273             :          * ORDER BY expressions using the fetched tuple.
     274             :          */
     275       86884 :         if (scandesc->xs_recheck)
     276             :         {
     277        9126 :             econtext->ecxt_scantuple = slot;
     278        9126 :             if (!ExecQualAndReset(node->indexqualorig, econtext))
     279             :             {
     280             :                 /* Fails recheck, so drop it and loop back for another */
     281        4140 :                 InstrCountFiltered2(node, 1);
     282             :                 /* allow this loop to be cancellable */
     283        4140 :                 CHECK_FOR_INTERRUPTS();
     284        4140 :                 goto next_indextuple;
     285             :             }
     286             :         }
     287             : 
     288       82744 :         if (scandesc->xs_recheckorderby)
     289             :         {
     290        5300 :             econtext->ecxt_scantuple = slot;
     291        5300 :             ResetExprContext(econtext);
     292        5300 :             EvalOrderByExpressions(node, econtext);
     293             : 
     294             :             /*
     295             :              * Was the ORDER BY value returned by the index accurate?  The
     296             :              * recheck flag means that the index can return inaccurate values,
     297             :              * but then again, the value returned for any particular tuple
     298             :              * could also be exactly correct.  Compare the value returned by
     299             :              * the index with the recalculated value.  (If the value returned
     300             :              * by the index happened to be exact right, we can often avoid
     301             :              * pushing the tuple to the queue, just to pop it back out again.)
     302             :              */
     303        5300 :             cmp = cmp_orderbyvals(node->iss_OrderByValues,
     304        5300 :                                   node->iss_OrderByNulls,
     305        5300 :                                   scandesc->xs_orderbyvals,
     306        5300 :                                   scandesc->xs_orderbynulls,
     307             :                                   node);
     308        5300 :             if (cmp < 0)
     309           0 :                 elog(ERROR, "index returned tuples in wrong order");
     310        5300 :             else if (cmp == 0)
     311         130 :                 was_exact = true;
     312             :             else
     313        5170 :                 was_exact = false;
     314        5300 :             lastfetched_vals = node->iss_OrderByValues;
     315        5300 :             lastfetched_nulls = node->iss_OrderByNulls;
     316             :         }
     317             :         else
     318             :         {
     319       77444 :             was_exact = true;
     320       77444 :             lastfetched_vals = scandesc->xs_orderbyvals;
     321       77444 :             lastfetched_nulls = scandesc->xs_orderbynulls;
     322             :         }
     323             : 
     324             :         /*
     325             :          * Can we return this tuple immediately, or does it need to be pushed
     326             :          * to the reorder queue?  If the ORDER BY expression values returned
     327             :          * by the index were inaccurate, we can't return it yet, because the
     328             :          * next tuple from the index might need to come before this one. Also,
     329             :          * we can't return it yet if there are any smaller tuples in the queue
     330             :          * already.
     331             :          */
     332       82830 :         if (!was_exact || (topmost && cmp_orderbyvals(lastfetched_vals,
     333             :                                                       lastfetched_nulls,
     334          86 :                                                       topmost->orderbyvals,
     335          86 :                                                       topmost->orderbynulls,
     336             :                                                       node) > 0))
     337             :         {
     338             :             /* Put this tuple to the queue */
     339        5176 :             reorderqueue_push(node, slot, lastfetched_vals, lastfetched_nulls);
     340        5176 :             continue;
     341             :         }
     342             :         else
     343             :         {
     344             :             /* Can return this tuple immediately. */
     345       77568 :             return slot;
     346             :         }
     347             :     }
     348             : 
     349             :     /*
     350             :      * if we get here it means the index scan failed so we are at the end of
     351             :      * the scan..
     352             :      */
     353             :     return ExecClearTuple(slot);
     354             : }
     355             : 
     356             : /*
     357             :  * Calculate the expressions in the ORDER BY clause, based on the heap tuple.
     358             :  */
     359             : static void
     360        5300 : EvalOrderByExpressions(IndexScanState *node, ExprContext *econtext)
     361             : {
     362             :     int         i;
     363             :     ListCell   *l;
     364             :     MemoryContext oldContext;
     365             : 
     366        5300 :     oldContext = MemoryContextSwitchTo(econtext->ecxt_per_tuple_memory);
     367             : 
     368        5300 :     i = 0;
     369       10600 :     foreach(l, node->indexorderbyorig)
     370             :     {
     371        5300 :         ExprState  *orderby = (ExprState *) lfirst(l);
     372             : 
     373       10600 :         node->iss_OrderByValues[i] = ExecEvalExpr(orderby,
     374             :                                                   econtext,
     375        5300 :                                                   &node->iss_OrderByNulls[i]);
     376        5300 :         i++;
     377             :     }
     378             : 
     379        5300 :     MemoryContextSwitchTo(oldContext);
     380        5300 : }
     381             : 
     382             : /*
     383             :  * IndexRecheck -- access method routine to recheck a tuple in EvalPlanQual
     384             :  */
     385             : static bool
     386          96 : IndexRecheck(IndexScanState *node, TupleTableSlot *slot)
     387             : {
     388             :     ExprContext *econtext;
     389             : 
     390             :     /*
     391             :      * extract necessary information from index scan node
     392             :      */
     393          96 :     econtext = node->ss.ps.ps_ExprContext;
     394             : 
     395             :     /* Does the tuple meet the indexqual condition? */
     396          96 :     econtext->ecxt_scantuple = slot;
     397          96 :     return ExecQualAndReset(node->indexqualorig, econtext);
     398             : }
     399             : 
     400             : 
     401             : /*
     402             :  * Compare ORDER BY expression values.
     403             :  */
     404             : static int
     405       29224 : cmp_orderbyvals(const Datum *adist, const bool *anulls,
     406             :                 const Datum *bdist, const bool *bnulls,
     407             :                 IndexScanState *node)
     408             : {
     409             :     int         i;
     410             :     int         result;
     411             : 
     412       29412 :     for (i = 0; i < node->iss_NumOrderByKeys; i++)
     413             :     {
     414       29224 :         SortSupport ssup = &node->iss_SortSupport[i];
     415             : 
     416             :         /*
     417             :          * Handle nulls.  We only need to support NULLS LAST ordering, because
     418             :          * match_pathkeys_to_index() doesn't consider indexorderby
     419             :          * implementation otherwise.
     420             :          */
     421       29224 :         if (anulls[i] && !bnulls[i])
     422           0 :             return 1;
     423       29224 :         else if (!anulls[i] && bnulls[i])
     424           0 :             return -1;
     425       29224 :         else if (anulls[i] && bnulls[i])
     426           0 :             return 0;
     427             : 
     428       29224 :         result = ssup->comparator(adist[i], bdist[i], ssup);
     429       29224 :         if (result != 0)
     430       29036 :             return result;
     431             :     }
     432             : 
     433         188 :     return 0;
     434             : }
     435             : 
     436             : /*
     437             :  * Pairing heap provides getting topmost (greatest) element while KNN provides
     438             :  * ascending sort.  That's why we invert the sort order.
     439             :  */
     440             : static int
     441       13594 : reorderqueue_cmp(const pairingheap_node *a, const pairingheap_node *b,
     442             :                  void *arg)
     443             : {
     444       13594 :     ReorderTuple *rta = (ReorderTuple *) a;
     445       13594 :     ReorderTuple *rtb = (ReorderTuple *) b;
     446       13594 :     IndexScanState *node = (IndexScanState *) arg;
     447             : 
     448             :     /* exchange argument order to invert the sort order */
     449       27188 :     return cmp_orderbyvals(rtb->orderbyvals, rtb->orderbynulls,
     450       13594 :                            rta->orderbyvals, rta->orderbynulls,
     451             :                            node);
     452             : }
     453             : 
     454             : /*
     455             :  * Helper function to push a tuple to the reorder queue.
     456             :  */
     457             : static void
     458        5176 : reorderqueue_push(IndexScanState *node, TupleTableSlot *slot,
     459             :                   Datum *orderbyvals, bool *orderbynulls)
     460             : {
     461        5176 :     IndexScanDesc scandesc = node->iss_ScanDesc;
     462        5176 :     EState     *estate = node->ss.ps.state;
     463        5176 :     MemoryContext oldContext = MemoryContextSwitchTo(estate->es_query_cxt);
     464             :     ReorderTuple *rt;
     465             :     int         i;
     466             : 
     467        5176 :     rt = (ReorderTuple *) palloc(sizeof(ReorderTuple));
     468        5176 :     rt->htup = ExecCopySlotHeapTuple(slot);
     469        5176 :     rt->orderbyvals =
     470        5176 :         (Datum *) palloc(sizeof(Datum) * scandesc->numberOfOrderBys);
     471        5176 :     rt->orderbynulls =
     472        5176 :         (bool *) palloc(sizeof(bool) * scandesc->numberOfOrderBys);
     473       10352 :     for (i = 0; i < node->iss_NumOrderByKeys; i++)
     474             :     {
     475        5176 :         if (!orderbynulls[i])
     476        5176 :             rt->orderbyvals[i] = datumCopy(orderbyvals[i],
     477        5176 :                                            node->iss_OrderByTypByVals[i],
     478        5176 :                                            node->iss_OrderByTypLens[i]);
     479             :         else
     480           0 :             rt->orderbyvals[i] = (Datum) 0;
     481        5176 :         rt->orderbynulls[i] = orderbynulls[i];
     482             :     }
     483        5176 :     pairingheap_add(node->iss_ReorderQueue, &rt->ph_node);
     484             : 
     485        5176 :     MemoryContextSwitchTo(oldContext);
     486        5176 : }
     487             : 
     488             : /*
     489             :  * Helper function to pop the next tuple from the reorder queue.
     490             :  */
     491             : static HeapTuple
     492        5136 : reorderqueue_pop(IndexScanState *node)
     493             : {
     494             :     HeapTuple   result;
     495             :     ReorderTuple *topmost;
     496             :     int         i;
     497             : 
     498        5136 :     topmost = (ReorderTuple *) pairingheap_remove_first(node->iss_ReorderQueue);
     499             : 
     500        5136 :     result = topmost->htup;
     501       10272 :     for (i = 0; i < node->iss_NumOrderByKeys; i++)
     502             :     {
     503        5136 :         if (!node->iss_OrderByTypByVals[i] && !topmost->orderbynulls[i])
     504           0 :             pfree(DatumGetPointer(topmost->orderbyvals[i]));
     505             :     }
     506        5136 :     pfree(topmost->orderbyvals);
     507        5136 :     pfree(topmost->orderbynulls);
     508        5136 :     pfree(topmost);
     509             : 
     510        5136 :     return result;
     511             : }
     512             : 
     513             : 
     514             : /* ----------------------------------------------------------------
     515             :  *      ExecIndexScan(node)
     516             :  * ----------------------------------------------------------------
     517             :  */
     518             : static TupleTableSlot *
     519     1812074 : ExecIndexScan(PlanState *pstate)
     520             : {
     521     1812074 :     IndexScanState *node = castNode(IndexScanState, pstate);
     522             : 
     523             :     /*
     524             :      * If we have runtime keys and they've not already been set up, do it now.
     525             :      */
     526     1812074 :     if (node->iss_NumRuntimeKeys != 0 && !node->iss_RuntimeKeysReady)
     527       18030 :         ExecReScan((PlanState *) node);
     528             : 
     529     1812068 :     if (node->iss_NumOrderByKeys > 0)
     530       82662 :         return ExecScan(&node->ss,
     531             :                         (ExecScanAccessMtd) IndexNextWithReorder,
     532             :                         (ExecScanRecheckMtd) IndexRecheck);
     533             :     else
     534     1729406 :         return ExecScan(&node->ss,
     535             :                         (ExecScanAccessMtd) IndexNext,
     536             :                         (ExecScanRecheckMtd) IndexRecheck);
     537             : }
     538             : 
     539             : /* ----------------------------------------------------------------
     540             :  *      ExecReScanIndexScan(node)
     541             :  *
     542             :  *      Recalculates the values of any scan keys whose value depends on
     543             :  *      information known at runtime, then rescans the indexed relation.
     544             :  *
     545             :  *      Updating the scan key was formerly done separately in
     546             :  *      ExecUpdateIndexScanKeys. Integrating it into ReScan makes
     547             :  *      rescans of indices and relations/general streams more uniform.
     548             :  * ----------------------------------------------------------------
     549             :  */
     550             : void
     551      413312 : ExecReScanIndexScan(IndexScanState *node)
     552             : {
     553             :     /*
     554             :      * If we are doing runtime key calculations (ie, any of the index key
     555             :      * values weren't simple Consts), compute the new key values.  But first,
     556             :      * reset the context so we don't leak memory as each outer tuple is
     557             :      * scanned.  Note this assumes that we will recalculate *all* runtime keys
     558             :      * on each call.
     559             :      */
     560      413312 :     if (node->iss_NumRuntimeKeys != 0)
     561             :     {
     562      402382 :         ExprContext *econtext = node->iss_RuntimeContext;
     563             : 
     564      402382 :         ResetExprContext(econtext);
     565      402382 :         ExecIndexEvalRuntimeKeys(econtext,
     566             :                                  node->iss_RuntimeKeys,
     567             :                                  node->iss_NumRuntimeKeys);
     568             :     }
     569      413306 :     node->iss_RuntimeKeysReady = true;
     570             : 
     571             :     /* flush the reorder queue */
     572      413306 :     if (node->iss_ReorderQueue)
     573             :     {
     574             :         HeapTuple   tuple;
     575             : 
     576         126 :         while (!pairingheap_is_empty(node->iss_ReorderQueue))
     577             :         {
     578          60 :             tuple = reorderqueue_pop(node);
     579          60 :             heap_freetuple(tuple);
     580             :         }
     581             :     }
     582             : 
     583             :     /* reset index scan */
     584      413306 :     if (node->iss_ScanDesc)
     585      363452 :         index_rescan(node->iss_ScanDesc,
     586      363452 :                      node->iss_ScanKeys, node->iss_NumScanKeys,
     587      363452 :                      node->iss_OrderByKeys, node->iss_NumOrderByKeys);
     588      413306 :     node->iss_ReachedEnd = false;
     589             : 
     590      413306 :     ExecScanReScan(&node->ss);
     591      413306 : }
     592             : 
     593             : 
     594             : /*
     595             :  * ExecIndexEvalRuntimeKeys
     596             :  *      Evaluate any runtime key values, and update the scankeys.
     597             :  */
     598             : void
     599      498390 : ExecIndexEvalRuntimeKeys(ExprContext *econtext,
     600             :                          IndexRuntimeKeyInfo *runtimeKeys, int numRuntimeKeys)
     601             : {
     602             :     int         j;
     603             :     MemoryContext oldContext;
     604             : 
     605             :     /* We want to keep the key values in per-tuple memory */
     606      498390 :     oldContext = MemoryContextSwitchTo(econtext->ecxt_per_tuple_memory);
     607             : 
     608     1017660 :     for (j = 0; j < numRuntimeKeys; j++)
     609             :     {
     610      519276 :         ScanKey     scan_key = runtimeKeys[j].scan_key;
     611      519276 :         ExprState  *key_expr = runtimeKeys[j].key_expr;
     612             :         Datum       scanvalue;
     613             :         bool        isNull;
     614             : 
     615             :         /*
     616             :          * For each run-time key, extract the run-time expression and evaluate
     617             :          * it with respect to the current context.  We then stick the result
     618             :          * into the proper scan key.
     619             :          *
     620             :          * Note: the result of the eval could be a pass-by-ref value that's
     621             :          * stored in some outer scan's tuple, not in
     622             :          * econtext->ecxt_per_tuple_memory.  We assume that the outer tuple
     623             :          * will stay put throughout our scan.  If this is wrong, we could copy
     624             :          * the result into our context explicitly, but I think that's not
     625             :          * necessary.
     626             :          *
     627             :          * It's also entirely possible that the result of the eval is a
     628             :          * toasted value.  In this case we should forcibly detoast it, to
     629             :          * avoid repeat detoastings each time the value is examined by an
     630             :          * index support function.
     631             :          */
     632      519276 :         scanvalue = ExecEvalExpr(key_expr,
     633             :                                  econtext,
     634             :                                  &isNull);
     635      519270 :         if (isNull)
     636             :         {
     637        2670 :             scan_key->sk_argument = scanvalue;
     638        2670 :             scan_key->sk_flags |= SK_ISNULL;
     639             :         }
     640             :         else
     641             :         {
     642      516600 :             if (runtimeKeys[j].key_toastable)
     643        3594 :                 scanvalue = PointerGetDatum(PG_DETOAST_DATUM(scanvalue));
     644      516600 :             scan_key->sk_argument = scanvalue;
     645      516600 :             scan_key->sk_flags &= ~SK_ISNULL;
     646             :         }
     647             :     }
     648             : 
     649      498384 :     MemoryContextSwitchTo(oldContext);
     650      498384 : }
     651             : 
     652             : /*
     653             :  * ExecIndexEvalArrayKeys
     654             :  *      Evaluate any array key values, and set up to iterate through arrays.
     655             :  *
     656             :  * Returns true if there are array elements to consider; false means there
     657             :  * is at least one null or empty array, so no match is possible.  On true
     658             :  * result, the scankeys are initialized with the first elements of the arrays.
     659             :  */
     660             : bool
     661          26 : ExecIndexEvalArrayKeys(ExprContext *econtext,
     662             :                        IndexArrayKeyInfo *arrayKeys, int numArrayKeys)
     663             : {
     664          26 :     bool        result = true;
     665             :     int         j;
     666             :     MemoryContext oldContext;
     667             : 
     668             :     /* We want to keep the arrays in per-tuple memory */
     669          26 :     oldContext = MemoryContextSwitchTo(econtext->ecxt_per_tuple_memory);
     670             : 
     671          52 :     for (j = 0; j < numArrayKeys; j++)
     672             :     {
     673          26 :         ScanKey     scan_key = arrayKeys[j].scan_key;
     674          26 :         ExprState  *array_expr = arrayKeys[j].array_expr;
     675             :         Datum       arraydatum;
     676             :         bool        isNull;
     677             :         ArrayType  *arrayval;
     678             :         int16       elmlen;
     679             :         bool        elmbyval;
     680             :         char        elmalign;
     681             :         int         num_elems;
     682             :         Datum      *elem_values;
     683             :         bool       *elem_nulls;
     684             : 
     685             :         /*
     686             :          * Compute and deconstruct the array expression. (Notes in
     687             :          * ExecIndexEvalRuntimeKeys() apply here too.)
     688             :          */
     689          26 :         arraydatum = ExecEvalExpr(array_expr,
     690             :                                   econtext,
     691             :                                   &isNull);
     692          26 :         if (isNull)
     693             :         {
     694           0 :             result = false;
     695           0 :             break;              /* no point in evaluating more */
     696             :         }
     697          26 :         arrayval = DatumGetArrayTypeP(arraydatum);
     698             :         /* We could cache this data, but not clear it's worth it */
     699          26 :         get_typlenbyvalalign(ARR_ELEMTYPE(arrayval),
     700             :                              &elmlen, &elmbyval, &elmalign);
     701          26 :         deconstruct_array(arrayval,
     702             :                           ARR_ELEMTYPE(arrayval),
     703             :                           elmlen, elmbyval, elmalign,
     704             :                           &elem_values, &elem_nulls, &num_elems);
     705          26 :         if (num_elems <= 0)
     706             :         {
     707           0 :             result = false;
     708           0 :             break;              /* no point in evaluating more */
     709             :         }
     710             : 
     711             :         /*
     712             :          * Note: we expect the previous array data, if any, to be
     713             :          * automatically freed by resetting the per-tuple context; hence no
     714             :          * pfree's here.
     715             :          */
     716          26 :         arrayKeys[j].elem_values = elem_values;
     717          26 :         arrayKeys[j].elem_nulls = elem_nulls;
     718          26 :         arrayKeys[j].num_elems = num_elems;
     719          26 :         scan_key->sk_argument = elem_values[0];
     720          26 :         if (elem_nulls[0])
     721           0 :             scan_key->sk_flags |= SK_ISNULL;
     722             :         else
     723          26 :             scan_key->sk_flags &= ~SK_ISNULL;
     724          26 :         arrayKeys[j].next_elem = 1;
     725             :     }
     726             : 
     727          26 :     MemoryContextSwitchTo(oldContext);
     728             : 
     729          26 :     return result;
     730             : }
     731             : 
     732             : /*
     733             :  * ExecIndexAdvanceArrayKeys
     734             :  *      Advance to the next set of array key values, if any.
     735             :  *
     736             :  * Returns true if there is another set of values to consider, false if not.
     737             :  * On true result, the scankeys are initialized with the next set of values.
     738             :  */
     739             : bool
     740       20888 : ExecIndexAdvanceArrayKeys(IndexArrayKeyInfo *arrayKeys, int numArrayKeys)
     741             : {
     742       20888 :     bool        found = false;
     743             :     int         j;
     744             : 
     745             :     /*
     746             :      * Note we advance the rightmost array key most quickly, since it will
     747             :      * correspond to the lowest-order index column among the available
     748             :      * qualifications.  This is hypothesized to result in better locality of
     749             :      * access in the index.
     750             :      */
     751       20914 :     for (j = numArrayKeys - 1; j >= 0; j--)
     752             :     {
     753          52 :         ScanKey     scan_key = arrayKeys[j].scan_key;
     754          52 :         int         next_elem = arrayKeys[j].next_elem;
     755          52 :         int         num_elems = arrayKeys[j].num_elems;
     756          52 :         Datum      *elem_values = arrayKeys[j].elem_values;
     757          52 :         bool       *elem_nulls = arrayKeys[j].elem_nulls;
     758             : 
     759          52 :         if (next_elem >= num_elems)
     760             :         {
     761          26 :             next_elem = 0;
     762          26 :             found = false;      /* need to advance next array key */
     763             :         }
     764             :         else
     765          26 :             found = true;
     766          52 :         scan_key->sk_argument = elem_values[next_elem];
     767          52 :         if (elem_nulls[next_elem])
     768           0 :             scan_key->sk_flags |= SK_ISNULL;
     769             :         else
     770          52 :             scan_key->sk_flags &= ~SK_ISNULL;
     771          52 :         arrayKeys[j].next_elem = next_elem + 1;
     772          52 :         if (found)
     773          26 :             break;
     774             :     }
     775             : 
     776       20888 :     return found;
     777             : }
     778             : 
     779             : 
     780             : /* ----------------------------------------------------------------
     781             :  *      ExecEndIndexScan
     782             :  * ----------------------------------------------------------------
     783             :  */
     784             : void
     785      142764 : ExecEndIndexScan(IndexScanState *node)
     786             : {
     787             :     Relation    indexRelationDesc;
     788             :     IndexScanDesc indexScanDesc;
     789             : 
     790             :     /*
     791             :      * extract information from the node
     792             :      */
     793      142764 :     indexRelationDesc = node->iss_RelationDesc;
     794      142764 :     indexScanDesc = node->iss_ScanDesc;
     795             : 
     796             :     /*
     797             :      * close the index relation (no-op if we didn't open it)
     798             :      */
     799      142764 :     if (indexScanDesc)
     800      117010 :         index_endscan(indexScanDesc);
     801      142764 :     if (indexRelationDesc)
     802      139788 :         index_close(indexRelationDesc, NoLock);
     803      142764 : }
     804             : 
     805             : /* ----------------------------------------------------------------
     806             :  *      ExecIndexMarkPos
     807             :  *
     808             :  * Note: we assume that no caller attempts to set a mark before having read
     809             :  * at least one tuple.  Otherwise, iss_ScanDesc might still be NULL.
     810             :  * ----------------------------------------------------------------
     811             :  */
     812             : void
     813        6040 : ExecIndexMarkPos(IndexScanState *node)
     814             : {
     815        6040 :     EState     *estate = node->ss.ps.state;
     816        6040 :     EPQState   *epqstate = estate->es_epq_active;
     817             : 
     818        6040 :     if (epqstate != NULL)
     819             :     {
     820             :         /*
     821             :          * We are inside an EvalPlanQual recheck.  If a test tuple exists for
     822             :          * this relation, then we shouldn't access the index at all.  We would
     823             :          * instead need to save, and later restore, the state of the
     824             :          * relsubs_done flag, so that re-fetching the test tuple is possible.
     825             :          * However, given the assumption that no caller sets a mark at the
     826             :          * start of the scan, we can only get here with relsubs_done[i]
     827             :          * already set, and so no state need be saved.
     828             :          */
     829           2 :         Index       scanrelid = ((Scan *) node->ss.ps.plan)->scanrelid;
     830             : 
     831             :         Assert(scanrelid > 0);
     832           2 :         if (epqstate->relsubs_slot[scanrelid - 1] != NULL ||
     833           0 :             epqstate->relsubs_rowmark[scanrelid - 1] != NULL)
     834             :         {
     835             :             /* Verify the claim above */
     836           2 :             if (!epqstate->relsubs_done[scanrelid - 1])
     837           0 :                 elog(ERROR, "unexpected ExecIndexMarkPos call in EPQ recheck");
     838           2 :             return;
     839             :         }
     840             :     }
     841             : 
     842        6038 :     index_markpos(node->iss_ScanDesc);
     843             : }
     844             : 
     845             : /* ----------------------------------------------------------------
     846             :  *      ExecIndexRestrPos
     847             :  * ----------------------------------------------------------------
     848             :  */
     849             : void
     850       54018 : ExecIndexRestrPos(IndexScanState *node)
     851             : {
     852       54018 :     EState     *estate = node->ss.ps.state;
     853       54018 :     EPQState   *epqstate = estate->es_epq_active;
     854             : 
     855       54018 :     if (estate->es_epq_active != NULL)
     856             :     {
     857             :         /* See comments in ExecIndexMarkPos */
     858           0 :         Index       scanrelid = ((Scan *) node->ss.ps.plan)->scanrelid;
     859             : 
     860             :         Assert(scanrelid > 0);
     861           0 :         if (epqstate->relsubs_slot[scanrelid - 1] != NULL ||
     862           0 :             epqstate->relsubs_rowmark[scanrelid - 1] != NULL)
     863             :         {
     864             :             /* Verify the claim above */
     865           0 :             if (!epqstate->relsubs_done[scanrelid - 1])
     866           0 :                 elog(ERROR, "unexpected ExecIndexRestrPos call in EPQ recheck");
     867           0 :             return;
     868             :         }
     869             :     }
     870             : 
     871       54018 :     index_restrpos(node->iss_ScanDesc);
     872             : }
     873             : 
     874             : /* ----------------------------------------------------------------
     875             :  *      ExecInitIndexScan
     876             :  *
     877             :  *      Initializes the index scan's state information, creates
     878             :  *      scan keys, and opens the base and index relations.
     879             :  *
     880             :  *      Note: index scans have 2 sets of state information because
     881             :  *            we have to keep track of the base relation and the
     882             :  *            index relation.
     883             :  * ----------------------------------------------------------------
     884             :  */
     885             : IndexScanState *
     886      143568 : ExecInitIndexScan(IndexScan *node, EState *estate, int eflags)
     887             : {
     888             :     IndexScanState *indexstate;
     889             :     Relation    currentRelation;
     890             :     LOCKMODE    lockmode;
     891             : 
     892             :     /*
     893             :      * create state structure
     894             :      */
     895      143568 :     indexstate = makeNode(IndexScanState);
     896      143568 :     indexstate->ss.ps.plan = (Plan *) node;
     897      143568 :     indexstate->ss.ps.state = estate;
     898      143568 :     indexstate->ss.ps.ExecProcNode = ExecIndexScan;
     899             : 
     900             :     /*
     901             :      * Miscellaneous initialization
     902             :      *
     903             :      * create expression context for node
     904             :      */
     905      143568 :     ExecAssignExprContext(estate, &indexstate->ss.ps);
     906             : 
     907             :     /*
     908             :      * open the scan relation
     909             :      */
     910      143568 :     currentRelation = ExecOpenScanRelation(estate, node->scan.scanrelid, eflags);
     911             : 
     912      143568 :     indexstate->ss.ss_currentRelation = currentRelation;
     913      143568 :     indexstate->ss.ss_currentScanDesc = NULL;    /* no heap scan here */
     914             : 
     915             :     /*
     916             :      * get the scan type from the relation descriptor.
     917             :      */
     918      143568 :     ExecInitScanTupleSlot(estate, &indexstate->ss,
     919             :                           RelationGetDescr(currentRelation),
     920             :                           table_slot_callbacks(currentRelation));
     921             : 
     922             :     /*
     923             :      * Initialize result type and projection.
     924             :      */
     925      143568 :     ExecInitResultTypeTL(&indexstate->ss.ps);
     926      143568 :     ExecAssignScanProjectionInfo(&indexstate->ss);
     927             : 
     928             :     /*
     929             :      * initialize child expressions
     930             :      *
     931             :      * Note: we don't initialize all of the indexqual expression, only the
     932             :      * sub-parts corresponding to runtime keys (see below).  Likewise for
     933             :      * indexorderby, if any.  But the indexqualorig expression is always
     934             :      * initialized even though it will only be used in some uncommon cases ---
     935             :      * would be nice to improve that.  (Problem is that any SubPlans present
     936             :      * in the expression must be found now...)
     937             :      */
     938      143568 :     indexstate->ss.ps.qual =
     939      143568 :         ExecInitQual(node->scan.plan.qual, (PlanState *) indexstate);
     940      143568 :     indexstate->indexqualorig =
     941      143568 :         ExecInitQual(node->indexqualorig, (PlanState *) indexstate);
     942      143568 :     indexstate->indexorderbyorig =
     943      143568 :         ExecInitExprList(node->indexorderbyorig, (PlanState *) indexstate);
     944             : 
     945             :     /*
     946             :      * If we are just doing EXPLAIN (ie, aren't going to run the plan), stop
     947             :      * here.  This allows an index-advisor plugin to EXPLAIN a plan containing
     948             :      * references to nonexistent indexes.
     949             :      */
     950      143568 :     if (eflags & EXEC_FLAG_EXPLAIN_ONLY)
     951        2976 :         return indexstate;
     952             : 
     953             :     /* Open the index relation. */
     954      140592 :     lockmode = exec_rt_fetch(node->scan.scanrelid, estate)->rellockmode;
     955      140592 :     indexstate->iss_RelationDesc = index_open(node->indexid, lockmode);
     956             : 
     957             :     /*
     958             :      * Initialize index-specific scan state
     959             :      */
     960      140592 :     indexstate->iss_RuntimeKeysReady = false;
     961      140592 :     indexstate->iss_RuntimeKeys = NULL;
     962      140592 :     indexstate->iss_NumRuntimeKeys = 0;
     963             : 
     964             :     /*
     965             :      * build the index scan keys from the index qualification
     966             :      */
     967      140592 :     ExecIndexBuildScanKeys((PlanState *) indexstate,
     968             :                            indexstate->iss_RelationDesc,
     969             :                            node->indexqual,
     970             :                            false,
     971      140592 :                            &indexstate->iss_ScanKeys,
     972             :                            &indexstate->iss_NumScanKeys,
     973             :                            &indexstate->iss_RuntimeKeys,
     974             :                            &indexstate->iss_NumRuntimeKeys,
     975             :                            NULL,    /* no ArrayKeys */
     976             :                            NULL);
     977             : 
     978             :     /*
     979             :      * any ORDER BY exprs have to be turned into scankeys in the same way
     980             :      */
     981      140592 :     ExecIndexBuildScanKeys((PlanState *) indexstate,
     982             :                            indexstate->iss_RelationDesc,
     983             :                            node->indexorderby,
     984             :                            true,
     985      140592 :                            &indexstate->iss_OrderByKeys,
     986             :                            &indexstate->iss_NumOrderByKeys,
     987             :                            &indexstate->iss_RuntimeKeys,
     988             :                            &indexstate->iss_NumRuntimeKeys,
     989             :                            NULL,    /* no ArrayKeys */
     990             :                            NULL);
     991             : 
     992             :     /* Initialize sort support, if we need to re-check ORDER BY exprs */
     993      140592 :     if (indexstate->iss_NumOrderByKeys > 0)
     994             :     {
     995          46 :         int         numOrderByKeys = indexstate->iss_NumOrderByKeys;
     996             :         int         i;
     997             :         ListCell   *lco;
     998             :         ListCell   *lcx;
     999             : 
    1000             :         /*
    1001             :          * Prepare sort support, and look up the data type for each ORDER BY
    1002             :          * expression.
    1003             :          */
    1004             :         Assert(numOrderByKeys == list_length(node->indexorderbyops));
    1005             :         Assert(numOrderByKeys == list_length(node->indexorderbyorig));
    1006          46 :         indexstate->iss_SortSupport = (SortSupportData *)
    1007          46 :             palloc0(numOrderByKeys * sizeof(SortSupportData));
    1008          46 :         indexstate->iss_OrderByTypByVals = (bool *)
    1009          46 :             palloc(numOrderByKeys * sizeof(bool));
    1010          46 :         indexstate->iss_OrderByTypLens = (int16 *)
    1011          46 :             palloc(numOrderByKeys * sizeof(int16));
    1012          46 :         i = 0;
    1013          92 :         forboth(lco, node->indexorderbyops, lcx, node->indexorderbyorig)
    1014             :         {
    1015          46 :             Oid         orderbyop = lfirst_oid(lco);
    1016          46 :             Node       *orderbyexpr = (Node *) lfirst(lcx);
    1017          46 :             Oid         orderbyType = exprType(orderbyexpr);
    1018          46 :             Oid         orderbyColl = exprCollation(orderbyexpr);
    1019          46 :             SortSupport orderbysort = &indexstate->iss_SortSupport[i];
    1020             : 
    1021             :             /* Initialize sort support */
    1022          46 :             orderbysort->ssup_cxt = CurrentMemoryContext;
    1023          46 :             orderbysort->ssup_collation = orderbyColl;
    1024             :             /* See cmp_orderbyvals() comments on NULLS LAST */
    1025          46 :             orderbysort->ssup_nulls_first = false;
    1026             :             /* ssup_attno is unused here and elsewhere */
    1027          46 :             orderbysort->ssup_attno = 0;
    1028             :             /* No abbreviation */
    1029          46 :             orderbysort->abbreviate = false;
    1030          46 :             PrepareSortSupportFromOrderingOp(orderbyop, orderbysort);
    1031             : 
    1032          46 :             get_typlenbyval(orderbyType,
    1033          46 :                             &indexstate->iss_OrderByTypLens[i],
    1034          46 :                             &indexstate->iss_OrderByTypByVals[i]);
    1035          46 :             i++;
    1036             :         }
    1037             : 
    1038             :         /* allocate arrays to hold the re-calculated distances */
    1039          46 :         indexstate->iss_OrderByValues = (Datum *)
    1040          46 :             palloc(numOrderByKeys * sizeof(Datum));
    1041          46 :         indexstate->iss_OrderByNulls = (bool *)
    1042          46 :             palloc(numOrderByKeys * sizeof(bool));
    1043             : 
    1044             :         /* and initialize the reorder queue */
    1045          46 :         indexstate->iss_ReorderQueue = pairingheap_allocate(reorderqueue_cmp,
    1046             :                                                             indexstate);
    1047             :     }
    1048             : 
    1049             :     /*
    1050             :      * If we have runtime keys, we need an ExprContext to evaluate them. The
    1051             :      * node's standard context won't do because we want to reset that context
    1052             :      * for every tuple.  So, build another context just like the other one...
    1053             :      * -tgl 7/11/00
    1054             :      */
    1055      140592 :     if (indexstate->iss_NumRuntimeKeys != 0)
    1056             :     {
    1057       61316 :         ExprContext *stdecontext = indexstate->ss.ps.ps_ExprContext;
    1058             : 
    1059       61316 :         ExecAssignExprContext(estate, &indexstate->ss.ps);
    1060       61316 :         indexstate->iss_RuntimeContext = indexstate->ss.ps.ps_ExprContext;
    1061       61316 :         indexstate->ss.ps.ps_ExprContext = stdecontext;
    1062             :     }
    1063             :     else
    1064             :     {
    1065       79276 :         indexstate->iss_RuntimeContext = NULL;
    1066             :     }
    1067             : 
    1068             :     /*
    1069             :      * all done.
    1070             :      */
    1071      140592 :     return indexstate;
    1072             : }
    1073             : 
    1074             : 
    1075             : /*
    1076             :  * ExecIndexBuildScanKeys
    1077             :  *      Build the index scan keys from the index qualification expressions
    1078             :  *
    1079             :  * The index quals are passed to the index AM in the form of a ScanKey array.
    1080             :  * This routine sets up the ScanKeys, fills in all constant fields of the
    1081             :  * ScanKeys, and prepares information about the keys that have non-constant
    1082             :  * comparison values.  We divide index qual expressions into five types:
    1083             :  *
    1084             :  * 1. Simple operator with constant comparison value ("indexkey op constant").
    1085             :  * For these, we just fill in a ScanKey containing the constant value.
    1086             :  *
    1087             :  * 2. Simple operator with non-constant value ("indexkey op expression").
    1088             :  * For these, we create a ScanKey with everything filled in except the
    1089             :  * expression value, and set up an IndexRuntimeKeyInfo struct to drive
    1090             :  * evaluation of the expression at the right times.
    1091             :  *
    1092             :  * 3. RowCompareExpr ("(indexkey, indexkey, ...) op (expr, expr, ...)").
    1093             :  * For these, we create a header ScanKey plus a subsidiary ScanKey array,
    1094             :  * as specified in access/skey.h.  The elements of the row comparison
    1095             :  * can have either constant or non-constant comparison values.
    1096             :  *
    1097             :  * 4. ScalarArrayOpExpr ("indexkey op ANY (array-expression)").  If the index
    1098             :  * supports amsearcharray, we handle these the same as simple operators,
    1099             :  * setting the SK_SEARCHARRAY flag to tell the AM to handle them.  Otherwise,
    1100             :  * we create a ScanKey with everything filled in except the comparison value,
    1101             :  * and set up an IndexArrayKeyInfo struct to drive processing of the qual.
    1102             :  * (Note that if we use an IndexArrayKeyInfo struct, the array expression is
    1103             :  * always treated as requiring runtime evaluation, even if it's a constant.)
    1104             :  *
    1105             :  * 5. NullTest ("indexkey IS NULL/IS NOT NULL").  We just fill in the
    1106             :  * ScanKey properly.
    1107             :  *
    1108             :  * This code is also used to prepare ORDER BY expressions for amcanorderbyop
    1109             :  * indexes.  The behavior is exactly the same, except that we have to look up
    1110             :  * the operator differently.  Note that only cases 1 and 2 are currently
    1111             :  * possible for ORDER BY.
    1112             :  *
    1113             :  * Input params are:
    1114             :  *
    1115             :  * planstate: executor state node we are working for
    1116             :  * index: the index we are building scan keys for
    1117             :  * quals: indexquals (or indexorderbys) expressions
    1118             :  * isorderby: true if processing ORDER BY exprs, false if processing quals
    1119             :  * *runtimeKeys: ptr to pre-existing IndexRuntimeKeyInfos, or NULL if none
    1120             :  * *numRuntimeKeys: number of pre-existing runtime keys
    1121             :  *
    1122             :  * Output params are:
    1123             :  *
    1124             :  * *scanKeys: receives ptr to array of ScanKeys
    1125             :  * *numScanKeys: receives number of scankeys
    1126             :  * *runtimeKeys: receives ptr to array of IndexRuntimeKeyInfos, or NULL if none
    1127             :  * *numRuntimeKeys: receives number of runtime keys
    1128             :  * *arrayKeys: receives ptr to array of IndexArrayKeyInfos, or NULL if none
    1129             :  * *numArrayKeys: receives number of array keys
    1130             :  *
    1131             :  * Caller may pass NULL for arrayKeys and numArrayKeys to indicate that
    1132             :  * IndexArrayKeyInfos are not supported.
    1133             :  */
    1134             : void
    1135      325898 : ExecIndexBuildScanKeys(PlanState *planstate, Relation index,
    1136             :                        List *quals, bool isorderby,
    1137             :                        ScanKey *scanKeys, int *numScanKeys,
    1138             :                        IndexRuntimeKeyInfo **runtimeKeys, int *numRuntimeKeys,
    1139             :                        IndexArrayKeyInfo **arrayKeys, int *numArrayKeys)
    1140             : {
    1141             :     ListCell   *qual_cell;
    1142             :     ScanKey     scan_keys;
    1143             :     IndexRuntimeKeyInfo *runtime_keys;
    1144             :     IndexArrayKeyInfo *array_keys;
    1145             :     int         n_scan_keys;
    1146             :     int         n_runtime_keys;
    1147             :     int         max_runtime_keys;
    1148             :     int         n_array_keys;
    1149             :     int         j;
    1150             : 
    1151             :     /* Allocate array for ScanKey structs: one per qual */
    1152      325898 :     n_scan_keys = list_length(quals);
    1153      325898 :     scan_keys = (ScanKey) palloc(n_scan_keys * sizeof(ScanKeyData));
    1154             : 
    1155             :     /*
    1156             :      * runtime_keys array is dynamically resized as needed.  We handle it this
    1157             :      * way so that the same runtime keys array can be shared between
    1158             :      * indexquals and indexorderbys, which will be processed in separate calls
    1159             :      * of this function.  Caller must be sure to pass in NULL/0 for first
    1160             :      * call.
    1161             :      */
    1162      325898 :     runtime_keys = *runtimeKeys;
    1163      325898 :     n_runtime_keys = max_runtime_keys = *numRuntimeKeys;
    1164             : 
    1165             :     /* Allocate array_keys as large as it could possibly need to be */
    1166             :     array_keys = (IndexArrayKeyInfo *)
    1167      325898 :         palloc0(n_scan_keys * sizeof(IndexArrayKeyInfo));
    1168      325898 :     n_array_keys = 0;
    1169             : 
    1170             :     /*
    1171             :      * for each opclause in the given qual, convert the opclause into a single
    1172             :      * scan key
    1173             :      */
    1174      325898 :     j = 0;
    1175      521182 :     foreach(qual_cell, quals)
    1176             :     {
    1177      195284 :         Expr       *clause = (Expr *) lfirst(qual_cell);
    1178      195284 :         ScanKey     this_scan_key = &scan_keys[j++];
    1179             :         Oid         opno;       /* operator's OID */
    1180             :         RegProcedure opfuncid;  /* operator proc id used in scan */
    1181             :         Oid         opfamily;   /* opfamily of index column */
    1182             :         int         op_strategy;    /* operator's strategy number */
    1183             :         Oid         op_lefttype;    /* operator's declared input types */
    1184             :         Oid         op_righttype;
    1185             :         Expr       *leftop;     /* expr on lhs of operator */
    1186             :         Expr       *rightop;    /* expr on rhs ... */
    1187             :         AttrNumber  varattno;   /* att number used in scan */
    1188             :         int         indnkeyatts;
    1189             : 
    1190      195284 :         indnkeyatts = IndexRelationGetNumberOfKeyAttributes(index);
    1191      195284 :         if (IsA(clause, OpExpr))
    1192             :         {
    1193             :             /* indexkey op const or indexkey op expression */
    1194      193674 :             int         flags = 0;
    1195             :             Datum       scanvalue;
    1196             : 
    1197      193674 :             opno = ((OpExpr *) clause)->opno;
    1198      193674 :             opfuncid = ((OpExpr *) clause)->opfuncid;
    1199             : 
    1200             :             /*
    1201             :              * leftop should be the index key Var, possibly relabeled
    1202             :              */
    1203      193674 :             leftop = (Expr *) get_leftop(clause);
    1204             : 
    1205      193674 :             if (leftop && IsA(leftop, RelabelType))
    1206           0 :                 leftop = ((RelabelType *) leftop)->arg;
    1207             : 
    1208             :             Assert(leftop != NULL);
    1209             : 
    1210      193674 :             if (!(IsA(leftop, Var) &&
    1211      193674 :                   ((Var *) leftop)->varno == INDEX_VAR))
    1212           0 :                 elog(ERROR, "indexqual doesn't have key on left side");
    1213             : 
    1214      193674 :             varattno = ((Var *) leftop)->varattno;
    1215      193674 :             if (varattno < 1 || varattno > indnkeyatts)
    1216           0 :                 elog(ERROR, "bogus index qualification");
    1217             : 
    1218             :             /*
    1219             :              * We have to look up the operator's strategy number.  This
    1220             :              * provides a cross-check that the operator does match the index.
    1221             :              */
    1222      193674 :             opfamily = index->rd_opfamily[varattno - 1];
    1223             : 
    1224      193674 :             get_op_opfamily_properties(opno, opfamily, isorderby,
    1225             :                                        &op_strategy,
    1226             :                                        &op_lefttype,
    1227             :                                        &op_righttype);
    1228             : 
    1229      193674 :             if (isorderby)
    1230         198 :                 flags |= SK_ORDER_BY;
    1231             : 
    1232             :             /*
    1233             :              * rightop is the constant or variable comparison value
    1234             :              */
    1235      193674 :             rightop = (Expr *) get_rightop(clause);
    1236             : 
    1237      193674 :             if (rightop && IsA(rightop, RelabelType))
    1238         852 :                 rightop = ((RelabelType *) rightop)->arg;
    1239             : 
    1240             :             Assert(rightop != NULL);
    1241             : 
    1242      193674 :             if (IsA(rightop, Const))
    1243             :             {
    1244             :                 /* OK, simple constant comparison value */
    1245      117888 :                 scanvalue = ((Const *) rightop)->constvalue;
    1246      117888 :                 if (((Const *) rightop)->constisnull)
    1247           0 :                     flags |= SK_ISNULL;
    1248             :             }
    1249             :             else
    1250             :             {
    1251             :                 /* Need to treat this one as a runtime key */
    1252       75786 :                 if (n_runtime_keys >= max_runtime_keys)
    1253             :                 {
    1254       67264 :                     if (max_runtime_keys == 0)
    1255             :                     {
    1256       67258 :                         max_runtime_keys = 8;
    1257             :                         runtime_keys = (IndexRuntimeKeyInfo *)
    1258       67258 :                             palloc(max_runtime_keys * sizeof(IndexRuntimeKeyInfo));
    1259             :                     }
    1260             :                     else
    1261             :                     {
    1262           6 :                         max_runtime_keys *= 2;
    1263             :                         runtime_keys = (IndexRuntimeKeyInfo *)
    1264           6 :                             repalloc(runtime_keys, max_runtime_keys * sizeof(IndexRuntimeKeyInfo));
    1265             :                     }
    1266             :                 }
    1267       75786 :                 runtime_keys[n_runtime_keys].scan_key = this_scan_key;
    1268      151572 :                 runtime_keys[n_runtime_keys].key_expr =
    1269       75786 :                     ExecInitExpr(rightop, planstate);
    1270       75786 :                 runtime_keys[n_runtime_keys].key_toastable =
    1271       75786 :                     TypeIsToastable(op_righttype);
    1272       75786 :                 n_runtime_keys++;
    1273       75786 :                 scanvalue = (Datum) 0;
    1274             :             }
    1275             : 
    1276             :             /*
    1277             :              * initialize the scan key's fields appropriately
    1278             :              */
    1279      193674 :             ScanKeyEntryInitialize(this_scan_key,
    1280             :                                    flags,
    1281             :                                    varattno,    /* attribute number to scan */
    1282             :                                    op_strategy, /* op's strategy */
    1283             :                                    op_righttype,    /* strategy subtype */
    1284             :                                    ((OpExpr *) clause)->inputcollid, /* collation */
    1285             :                                    opfuncid,    /* reg proc to use */
    1286             :                                    scanvalue);  /* constant */
    1287             :         }
    1288        1610 :         else if (IsA(clause, RowCompareExpr))
    1289             :         {
    1290             :             /* (indexkey, indexkey, ...) op (expression, expression, ...) */
    1291          36 :             RowCompareExpr *rc = (RowCompareExpr *) clause;
    1292             :             ScanKey     first_sub_key;
    1293             :             int         n_sub_key;
    1294             :             ListCell   *largs_cell;
    1295             :             ListCell   *rargs_cell;
    1296             :             ListCell   *opnos_cell;
    1297             :             ListCell   *collids_cell;
    1298             : 
    1299             :             Assert(!isorderby);
    1300             : 
    1301             :             first_sub_key = (ScanKey)
    1302          36 :                 palloc(list_length(rc->opnos) * sizeof(ScanKeyData));
    1303          36 :             n_sub_key = 0;
    1304             : 
    1305             :             /* Scan RowCompare columns and generate subsidiary ScanKey items */
    1306         108 :             forfour(largs_cell, rc->largs, rargs_cell, rc->rargs,
    1307             :                     opnos_cell, rc->opnos, collids_cell, rc->inputcollids)
    1308             :             {
    1309          72 :                 ScanKey     this_sub_key = &first_sub_key[n_sub_key];
    1310          72 :                 int         flags = SK_ROW_MEMBER;
    1311             :                 Datum       scanvalue;
    1312             :                 Oid         inputcollation;
    1313             : 
    1314          72 :                 leftop = (Expr *) lfirst(largs_cell);
    1315          72 :                 rightop = (Expr *) lfirst(rargs_cell);
    1316          72 :                 opno = lfirst_oid(opnos_cell);
    1317          72 :                 inputcollation = lfirst_oid(collids_cell);
    1318             : 
    1319             :                 /*
    1320             :                  * leftop should be the index key Var, possibly relabeled
    1321             :                  */
    1322          72 :                 if (leftop && IsA(leftop, RelabelType))
    1323           0 :                     leftop = ((RelabelType *) leftop)->arg;
    1324             : 
    1325             :                 Assert(leftop != NULL);
    1326             : 
    1327          72 :                 if (!(IsA(leftop, Var) &&
    1328          72 :                       ((Var *) leftop)->varno == INDEX_VAR))
    1329           0 :                     elog(ERROR, "indexqual doesn't have key on left side");
    1330             : 
    1331          72 :                 varattno = ((Var *) leftop)->varattno;
    1332             : 
    1333             :                 /*
    1334             :                  * We have to look up the operator's associated btree support
    1335             :                  * function
    1336             :                  */
    1337          72 :                 if (index->rd_rel->relam != BTREE_AM_OID ||
    1338          72 :                     varattno < 1 || varattno > indnkeyatts)
    1339           0 :                     elog(ERROR, "bogus RowCompare index qualification");
    1340          72 :                 opfamily = index->rd_opfamily[varattno - 1];
    1341             : 
    1342          72 :                 get_op_opfamily_properties(opno, opfamily, isorderby,
    1343             :                                            &op_strategy,
    1344             :                                            &op_lefttype,
    1345             :                                            &op_righttype);
    1346             : 
    1347          72 :                 if (op_strategy != rc->rctype)
    1348           0 :                     elog(ERROR, "RowCompare index qualification contains wrong operator");
    1349             : 
    1350          72 :                 opfuncid = get_opfamily_proc(opfamily,
    1351             :                                              op_lefttype,
    1352             :                                              op_righttype,
    1353             :                                              BTORDER_PROC);
    1354          72 :                 if (!RegProcedureIsValid(opfuncid))
    1355           0 :                     elog(ERROR, "missing support function %d(%u,%u) in opfamily %u",
    1356             :                          BTORDER_PROC, op_lefttype, op_righttype, opfamily);
    1357             : 
    1358             :                 /*
    1359             :                  * rightop is the constant or variable comparison value
    1360             :                  */
    1361          72 :                 if (rightop && IsA(rightop, RelabelType))
    1362           0 :                     rightop = ((RelabelType *) rightop)->arg;
    1363             : 
    1364             :                 Assert(rightop != NULL);
    1365             : 
    1366          72 :                 if (IsA(rightop, Const))
    1367             :                 {
    1368             :                     /* OK, simple constant comparison value */
    1369          72 :                     scanvalue = ((Const *) rightop)->constvalue;
    1370          72 :                     if (((Const *) rightop)->constisnull)
    1371           0 :                         flags |= SK_ISNULL;
    1372             :                 }
    1373             :                 else
    1374             :                 {
    1375             :                     /* Need to treat this one as a runtime key */
    1376           0 :                     if (n_runtime_keys >= max_runtime_keys)
    1377             :                     {
    1378           0 :                         if (max_runtime_keys == 0)
    1379             :                         {
    1380           0 :                             max_runtime_keys = 8;
    1381             :                             runtime_keys = (IndexRuntimeKeyInfo *)
    1382           0 :                                 palloc(max_runtime_keys * sizeof(IndexRuntimeKeyInfo));
    1383             :                         }
    1384             :                         else
    1385             :                         {
    1386           0 :                             max_runtime_keys *= 2;
    1387             :                             runtime_keys = (IndexRuntimeKeyInfo *)
    1388           0 :                                 repalloc(runtime_keys, max_runtime_keys * sizeof(IndexRuntimeKeyInfo));
    1389             :                         }
    1390             :                     }
    1391           0 :                     runtime_keys[n_runtime_keys].scan_key = this_sub_key;
    1392           0 :                     runtime_keys[n_runtime_keys].key_expr =
    1393           0 :                         ExecInitExpr(rightop, planstate);
    1394           0 :                     runtime_keys[n_runtime_keys].key_toastable =
    1395           0 :                         TypeIsToastable(op_righttype);
    1396           0 :                     n_runtime_keys++;
    1397           0 :                     scanvalue = (Datum) 0;
    1398             :                 }
    1399             : 
    1400             :                 /*
    1401             :                  * initialize the subsidiary scan key's fields appropriately
    1402             :                  */
    1403          72 :                 ScanKeyEntryInitialize(this_sub_key,
    1404             :                                        flags,
    1405             :                                        varattno,    /* attribute number */
    1406             :                                        op_strategy, /* op's strategy */
    1407             :                                        op_righttype,    /* strategy subtype */
    1408             :                                        inputcollation,  /* collation */
    1409             :                                        opfuncid,    /* reg proc to use */
    1410             :                                        scanvalue);  /* constant */
    1411          72 :                 n_sub_key++;
    1412             :             }
    1413             : 
    1414             :             /* Mark the last subsidiary scankey correctly */
    1415          36 :             first_sub_key[n_sub_key - 1].sk_flags |= SK_ROW_END;
    1416             : 
    1417             :             /*
    1418             :              * We don't use ScanKeyEntryInitialize for the header because it
    1419             :              * isn't going to contain a valid sk_func pointer.
    1420             :              */
    1421         360 :             MemSet(this_scan_key, 0, sizeof(ScanKeyData));
    1422          36 :             this_scan_key->sk_flags = SK_ROW_HEADER;
    1423          36 :             this_scan_key->sk_attno = first_sub_key->sk_attno;
    1424          36 :             this_scan_key->sk_strategy = rc->rctype;
    1425             :             /* sk_subtype, sk_collation, sk_func not used in a header */
    1426          36 :             this_scan_key->sk_argument = PointerGetDatum(first_sub_key);
    1427             :         }
    1428        1574 :         else if (IsA(clause, ScalarArrayOpExpr))
    1429             :         {
    1430             :             /* indexkey op ANY (array-expression) */
    1431        1046 :             ScalarArrayOpExpr *saop = (ScalarArrayOpExpr *) clause;
    1432        1046 :             int         flags = 0;
    1433             :             Datum       scanvalue;
    1434             : 
    1435             :             Assert(!isorderby);
    1436             : 
    1437             :             Assert(saop->useOr);
    1438        1046 :             opno = saop->opno;
    1439        1046 :             opfuncid = saop->opfuncid;
    1440             : 
    1441             :             /*
    1442             :              * leftop should be the index key Var, possibly relabeled
    1443             :              */
    1444        1046 :             leftop = (Expr *) linitial(saop->args);
    1445             : 
    1446        1046 :             if (leftop && IsA(leftop, RelabelType))
    1447           0 :                 leftop = ((RelabelType *) leftop)->arg;
    1448             : 
    1449             :             Assert(leftop != NULL);
    1450             : 
    1451        1046 :             if (!(IsA(leftop, Var) &&
    1452        1046 :                   ((Var *) leftop)->varno == INDEX_VAR))
    1453           0 :                 elog(ERROR, "indexqual doesn't have key on left side");
    1454             : 
    1455        1046 :             varattno = ((Var *) leftop)->varattno;
    1456        1046 :             if (varattno < 1 || varattno > indnkeyatts)
    1457           0 :                 elog(ERROR, "bogus index qualification");
    1458             : 
    1459             :             /*
    1460             :              * We have to look up the operator's strategy number.  This
    1461             :              * provides a cross-check that the operator does match the index.
    1462             :              */
    1463        1046 :             opfamily = index->rd_opfamily[varattno - 1];
    1464             : 
    1465        1046 :             get_op_opfamily_properties(opno, opfamily, isorderby,
    1466             :                                        &op_strategy,
    1467             :                                        &op_lefttype,
    1468             :                                        &op_righttype);
    1469             : 
    1470             :             /*
    1471             :              * rightop is the constant or variable array value
    1472             :              */
    1473        1046 :             rightop = (Expr *) lsecond(saop->args);
    1474             : 
    1475        1046 :             if (rightop && IsA(rightop, RelabelType))
    1476           0 :                 rightop = ((RelabelType *) rightop)->arg;
    1477             : 
    1478             :             Assert(rightop != NULL);
    1479             : 
    1480        1046 :             if (index->rd_indam->amsearcharray)
    1481             :             {
    1482             :                 /* Index AM will handle this like a simple operator */
    1483        1020 :                 flags |= SK_SEARCHARRAY;
    1484        1020 :                 if (IsA(rightop, Const))
    1485             :                 {
    1486             :                     /* OK, simple constant comparison value */
    1487         960 :                     scanvalue = ((Const *) rightop)->constvalue;
    1488         960 :                     if (((Const *) rightop)->constisnull)
    1489           0 :                         flags |= SK_ISNULL;
    1490             :                 }
    1491             :                 else
    1492             :                 {
    1493             :                     /* Need to treat this one as a runtime key */
    1494          60 :                     if (n_runtime_keys >= max_runtime_keys)
    1495             :                     {
    1496          60 :                         if (max_runtime_keys == 0)
    1497             :                         {
    1498          60 :                             max_runtime_keys = 8;
    1499             :                             runtime_keys = (IndexRuntimeKeyInfo *)
    1500          60 :                                 palloc(max_runtime_keys * sizeof(IndexRuntimeKeyInfo));
    1501             :                         }
    1502             :                         else
    1503             :                         {
    1504           0 :                             max_runtime_keys *= 2;
    1505             :                             runtime_keys = (IndexRuntimeKeyInfo *)
    1506           0 :                                 repalloc(runtime_keys, max_runtime_keys * sizeof(IndexRuntimeKeyInfo));
    1507             :                         }
    1508             :                     }
    1509          60 :                     runtime_keys[n_runtime_keys].scan_key = this_scan_key;
    1510         120 :                     runtime_keys[n_runtime_keys].key_expr =
    1511          60 :                         ExecInitExpr(rightop, planstate);
    1512             : 
    1513             :                     /*
    1514             :                      * Careful here: the runtime expression is not of
    1515             :                      * op_righttype, but rather is an array of same; so
    1516             :                      * TypeIsToastable() isn't helpful.  However, we can
    1517             :                      * assume that all array types are toastable.
    1518             :                      */
    1519          60 :                     runtime_keys[n_runtime_keys].key_toastable = true;
    1520          60 :                     n_runtime_keys++;
    1521          60 :                     scanvalue = (Datum) 0;
    1522             :                 }
    1523             :             }
    1524             :             else
    1525             :             {
    1526             :                 /* Executor has to expand the array value */
    1527          26 :                 array_keys[n_array_keys].scan_key = this_scan_key;
    1528          52 :                 array_keys[n_array_keys].array_expr =
    1529          26 :                     ExecInitExpr(rightop, planstate);
    1530             :                 /* the remaining fields were zeroed by palloc0 */
    1531          26 :                 n_array_keys++;
    1532          26 :                 scanvalue = (Datum) 0;
    1533             :             }
    1534             : 
    1535             :             /*
    1536             :              * initialize the scan key's fields appropriately
    1537             :              */
    1538        1046 :             ScanKeyEntryInitialize(this_scan_key,
    1539             :                                    flags,
    1540             :                                    varattno,    /* attribute number to scan */
    1541             :                                    op_strategy, /* op's strategy */
    1542             :                                    op_righttype,    /* strategy subtype */
    1543             :                                    saop->inputcollid,    /* collation */
    1544             :                                    opfuncid,    /* reg proc to use */
    1545             :                                    scanvalue);  /* constant */
    1546             :         }
    1547         528 :         else if (IsA(clause, NullTest))
    1548             :         {
    1549             :             /* indexkey IS NULL or indexkey IS NOT NULL */
    1550         528 :             NullTest   *ntest = (NullTest *) clause;
    1551             :             int         flags;
    1552             : 
    1553             :             Assert(!isorderby);
    1554             : 
    1555             :             /*
    1556             :              * argument should be the index key Var, possibly relabeled
    1557             :              */
    1558         528 :             leftop = ntest->arg;
    1559             : 
    1560         528 :             if (leftop && IsA(leftop, RelabelType))
    1561           0 :                 leftop = ((RelabelType *) leftop)->arg;
    1562             : 
    1563             :             Assert(leftop != NULL);
    1564             : 
    1565         528 :             if (!(IsA(leftop, Var) &&
    1566         528 :                   ((Var *) leftop)->varno == INDEX_VAR))
    1567           0 :                 elog(ERROR, "NullTest indexqual has wrong key");
    1568             : 
    1569         528 :             varattno = ((Var *) leftop)->varattno;
    1570             : 
    1571             :             /*
    1572             :              * initialize the scan key's fields appropriately
    1573             :              */
    1574         528 :             switch (ntest->nulltesttype)
    1575             :             {
    1576         182 :                 case IS_NULL:
    1577         182 :                     flags = SK_ISNULL | SK_SEARCHNULL;
    1578         182 :                     break;
    1579         346 :                 case IS_NOT_NULL:
    1580         346 :                     flags = SK_ISNULL | SK_SEARCHNOTNULL;
    1581         346 :                     break;
    1582           0 :                 default:
    1583           0 :                     elog(ERROR, "unrecognized nulltesttype: %d",
    1584             :                          (int) ntest->nulltesttype);
    1585             :                     flags = 0;  /* keep compiler quiet */
    1586             :                     break;
    1587             :             }
    1588             : 
    1589         528 :             ScanKeyEntryInitialize(this_scan_key,
    1590             :                                    flags,
    1591             :                                    varattno,    /* attribute number to scan */
    1592             :                                    InvalidStrategy, /* no strategy */
    1593             :                                    InvalidOid,  /* no strategy subtype */
    1594             :                                    InvalidOid,  /* no collation */
    1595             :                                    InvalidOid,  /* no reg proc for this */
    1596             :                                    (Datum) 0);  /* constant */
    1597             :         }
    1598             :         else
    1599           0 :             elog(ERROR, "unsupported indexqual type: %d",
    1600             :                  (int) nodeTag(clause));
    1601             :     }
    1602             : 
    1603             :     Assert(n_runtime_keys <= max_runtime_keys);
    1604             : 
    1605             :     /* Get rid of any unused arrays */
    1606      325898 :     if (n_array_keys == 0)
    1607             :     {
    1608      325872 :         pfree(array_keys);
    1609      325872 :         array_keys = NULL;
    1610             :     }
    1611             : 
    1612             :     /*
    1613             :      * Return info to our caller.
    1614             :      */
    1615      325898 :     *scanKeys = scan_keys;
    1616      325898 :     *numScanKeys = n_scan_keys;
    1617      325898 :     *runtimeKeys = runtime_keys;
    1618      325898 :     *numRuntimeKeys = n_runtime_keys;
    1619      325898 :     if (arrayKeys)
    1620             :     {
    1621       18266 :         *arrayKeys = array_keys;
    1622       18266 :         *numArrayKeys = n_array_keys;
    1623             :     }
    1624      307632 :     else if (n_array_keys != 0)
    1625           0 :         elog(ERROR, "ScalarArrayOpExpr index qual found where not allowed");
    1626      325898 : }
    1627             : 
    1628             : /* ----------------------------------------------------------------
    1629             :  *                      Parallel Scan Support
    1630             :  * ----------------------------------------------------------------
    1631             :  */
    1632             : 
    1633             : /* ----------------------------------------------------------------
    1634             :  *      ExecIndexScanEstimate
    1635             :  *
    1636             :  *      Compute the amount of space we'll need in the parallel
    1637             :  *      query DSM, and inform pcxt->estimator about our needs.
    1638             :  * ----------------------------------------------------------------
    1639             :  */
    1640             : void
    1641          18 : ExecIndexScanEstimate(IndexScanState *node,
    1642             :                       ParallelContext *pcxt)
    1643             : {
    1644          18 :     EState     *estate = node->ss.ps.state;
    1645             : 
    1646          18 :     node->iss_PscanLen = index_parallelscan_estimate(node->iss_RelationDesc,
    1647             :                                                      node->iss_NumScanKeys,
    1648             :                                                      node->iss_NumOrderByKeys,
    1649             :                                                      estate->es_snapshot);
    1650          18 :     shm_toc_estimate_chunk(&pcxt->estimator, node->iss_PscanLen);
    1651          18 :     shm_toc_estimate_keys(&pcxt->estimator, 1);
    1652          18 : }
    1653             : 
    1654             : /* ----------------------------------------------------------------
    1655             :  *      ExecIndexScanInitializeDSM
    1656             :  *
    1657             :  *      Set up a parallel index scan descriptor.
    1658             :  * ----------------------------------------------------------------
    1659             :  */
    1660             : void
    1661          18 : ExecIndexScanInitializeDSM(IndexScanState *node,
    1662             :                            ParallelContext *pcxt)
    1663             : {
    1664          18 :     EState     *estate = node->ss.ps.state;
    1665             :     ParallelIndexScanDesc piscan;
    1666             : 
    1667          18 :     piscan = shm_toc_allocate(pcxt->toc, node->iss_PscanLen);
    1668          18 :     index_parallelscan_initialize(node->ss.ss_currentRelation,
    1669             :                                   node->iss_RelationDesc,
    1670             :                                   estate->es_snapshot,
    1671             :                                   piscan);
    1672          18 :     shm_toc_insert(pcxt->toc, node->ss.ps.plan->plan_node_id, piscan);
    1673          18 :     node->iss_ScanDesc =
    1674          18 :         index_beginscan_parallel(node->ss.ss_currentRelation,
    1675             :                                  node->iss_RelationDesc,
    1676             :                                  node->iss_NumScanKeys,
    1677             :                                  node->iss_NumOrderByKeys,
    1678             :                                  piscan);
    1679             : 
    1680             :     /*
    1681             :      * If no run-time keys to calculate or they are ready, go ahead and pass
    1682             :      * the scankeys to the index AM.
    1683             :      */
    1684          18 :     if (node->iss_NumRuntimeKeys == 0 || node->iss_RuntimeKeysReady)
    1685          12 :         index_rescan(node->iss_ScanDesc,
    1686          12 :                      node->iss_ScanKeys, node->iss_NumScanKeys,
    1687          12 :                      node->iss_OrderByKeys, node->iss_NumOrderByKeys);
    1688          18 : }
    1689             : 
    1690             : /* ----------------------------------------------------------------
    1691             :  *      ExecIndexScanReInitializeDSM
    1692             :  *
    1693             :  *      Reset shared state before beginning a fresh scan.
    1694             :  * ----------------------------------------------------------------
    1695             :  */
    1696             : void
    1697          12 : ExecIndexScanReInitializeDSM(IndexScanState *node,
    1698             :                              ParallelContext *pcxt)
    1699             : {
    1700          12 :     index_parallelrescan(node->iss_ScanDesc);
    1701          12 : }
    1702             : 
    1703             : /* ----------------------------------------------------------------
    1704             :  *      ExecIndexScanInitializeWorker
    1705             :  *
    1706             :  *      Copy relevant information from TOC into planstate.
    1707             :  * ----------------------------------------------------------------
    1708             :  */
    1709             : void
    1710         120 : ExecIndexScanInitializeWorker(IndexScanState *node,
    1711             :                               ParallelWorkerContext *pwcxt)
    1712             : {
    1713             :     ParallelIndexScanDesc piscan;
    1714             : 
    1715         120 :     piscan = shm_toc_lookup(pwcxt->toc, node->ss.ps.plan->plan_node_id, false);
    1716         120 :     node->iss_ScanDesc =
    1717         120 :         index_beginscan_parallel(node->ss.ss_currentRelation,
    1718             :                                  node->iss_RelationDesc,
    1719             :                                  node->iss_NumScanKeys,
    1720             :                                  node->iss_NumOrderByKeys,
    1721             :                                  piscan);
    1722             : 
    1723             :     /*
    1724             :      * If no run-time keys to calculate or they are ready, go ahead and pass
    1725             :      * the scankeys to the index AM.
    1726             :      */
    1727         120 :     if (node->iss_NumRuntimeKeys == 0 || node->iss_RuntimeKeysReady)
    1728          96 :         index_rescan(node->iss_ScanDesc,
    1729          96 :                      node->iss_ScanKeys, node->iss_NumScanKeys,
    1730          96 :                      node->iss_OrderByKeys, node->iss_NumOrderByKeys);
    1731         120 : }

Generated by: LCOV version 1.14