Line data Source code
1 : /*-------------------------------------------------------------------------
2 : * attribute_stats.c
3 : *
4 : * PostgreSQL relation attribute statistics manipulation.
5 : *
6 : * Code supporting the direct import of relation attribute statistics, similar
7 : * to what is done by the ANALYZE command.
8 : *
9 : * Portions Copyright (c) 1996-2026, PostgreSQL Global Development Group
10 : * Portions Copyright (c) 1994, Regents of the University of California
11 : *
12 : * IDENTIFICATION
13 : * src/backend/statistics/attribute_stats.c
14 : *
15 : *-------------------------------------------------------------------------
16 : */
17 :
18 : #include "postgres.h"
19 :
20 : #include "access/heapam.h"
21 : #include "catalog/indexing.h"
22 : #include "catalog/namespace.h"
23 : #include "catalog/pg_operator.h"
24 : #include "nodes/makefuncs.h"
25 : #include "statistics/statistics.h"
26 : #include "statistics/stat_utils.h"
27 : #include "utils/array.h"
28 : #include "utils/builtins.h"
29 : #include "utils/fmgroids.h"
30 : #include "utils/lsyscache.h"
31 : #include "utils/syscache.h"
32 :
33 : /*
34 : * Positional argument numbers, names, and types for
35 : * attribute_statistics_update() and pg_restore_attribute_stats().
36 : */
37 :
38 : enum attribute_stats_argnum
39 : {
40 : ATTRELSCHEMA_ARG = 0,
41 : ATTRELNAME_ARG,
42 : ATTNAME_ARG,
43 : ATTNUM_ARG,
44 : INHERITED_ARG,
45 : NULL_FRAC_ARG,
46 : AVG_WIDTH_ARG,
47 : N_DISTINCT_ARG,
48 : MOST_COMMON_VALS_ARG,
49 : MOST_COMMON_FREQS_ARG,
50 : HISTOGRAM_BOUNDS_ARG,
51 : CORRELATION_ARG,
52 : MOST_COMMON_ELEMS_ARG,
53 : MOST_COMMON_ELEM_FREQS_ARG,
54 : ELEM_COUNT_HISTOGRAM_ARG,
55 : RANGE_LENGTH_HISTOGRAM_ARG,
56 : RANGE_EMPTY_FRAC_ARG,
57 : RANGE_BOUNDS_HISTOGRAM_ARG,
58 : NUM_ATTRIBUTE_STATS_ARGS
59 : };
60 :
61 : static struct StatsArgInfo attarginfo[] =
62 : {
63 : [ATTRELSCHEMA_ARG] = {"schemaname", TEXTOID},
64 : [ATTRELNAME_ARG] = {"relname", TEXTOID},
65 : [ATTNAME_ARG] = {"attname", TEXTOID},
66 : [ATTNUM_ARG] = {"attnum", INT2OID},
67 : [INHERITED_ARG] = {"inherited", BOOLOID},
68 : [NULL_FRAC_ARG] = {"null_frac", FLOAT4OID},
69 : [AVG_WIDTH_ARG] = {"avg_width", INT4OID},
70 : [N_DISTINCT_ARG] = {"n_distinct", FLOAT4OID},
71 : [MOST_COMMON_VALS_ARG] = {"most_common_vals", TEXTOID},
72 : [MOST_COMMON_FREQS_ARG] = {"most_common_freqs", FLOAT4ARRAYOID},
73 : [HISTOGRAM_BOUNDS_ARG] = {"histogram_bounds", TEXTOID},
74 : [CORRELATION_ARG] = {"correlation", FLOAT4OID},
75 : [MOST_COMMON_ELEMS_ARG] = {"most_common_elems", TEXTOID},
76 : [MOST_COMMON_ELEM_FREQS_ARG] = {"most_common_elem_freqs", FLOAT4ARRAYOID},
77 : [ELEM_COUNT_HISTOGRAM_ARG] = {"elem_count_histogram", FLOAT4ARRAYOID},
78 : [RANGE_LENGTH_HISTOGRAM_ARG] = {"range_length_histogram", TEXTOID},
79 : [RANGE_EMPTY_FRAC_ARG] = {"range_empty_frac", FLOAT4OID},
80 : [RANGE_BOUNDS_HISTOGRAM_ARG] = {"range_bounds_histogram", TEXTOID},
81 : [NUM_ATTRIBUTE_STATS_ARGS] = {0}
82 : };
83 :
84 : /*
85 : * Positional argument numbers, names, and types for
86 : * pg_clear_attribute_stats().
87 : */
88 :
89 : enum clear_attribute_stats_argnum
90 : {
91 : C_ATTRELSCHEMA_ARG = 0,
92 : C_ATTRELNAME_ARG,
93 : C_ATTNAME_ARG,
94 : C_INHERITED_ARG,
95 : C_NUM_ATTRIBUTE_STATS_ARGS
96 : };
97 :
98 : static struct StatsArgInfo cleararginfo[] =
99 : {
100 : [C_ATTRELSCHEMA_ARG] = {"relation", TEXTOID},
101 : [C_ATTRELNAME_ARG] = {"relation", TEXTOID},
102 : [C_ATTNAME_ARG] = {"attname", TEXTOID},
103 : [C_INHERITED_ARG] = {"inherited", BOOLOID},
104 : [C_NUM_ATTRIBUTE_STATS_ARGS] = {0}
105 : };
106 :
107 : static bool attribute_statistics_update(FunctionCallInfo fcinfo);
108 : static void upsert_pg_statistic(Relation starel, HeapTuple oldtup,
109 : const Datum *values, const bool *nulls, const bool *replaces);
110 : static bool delete_pg_statistic(Oid reloid, AttrNumber attnum, bool stainherit);
111 :
112 : /*
113 : * Insert or Update Attribute Statistics
114 : *
115 : * See pg_statistic.h for an explanation of how each statistic kind is
116 : * stored. Custom statistics kinds are not supported.
117 : *
118 : * Depending on the statistics kind, we need to derive information from the
119 : * attribute for which we're storing the stats. For instance, the MCVs are
120 : * stored as an anyarray, and the representation of the array needs to store
121 : * the correct element type, which must be derived from the attribute.
122 : *
123 : * Major errors, such as the table not existing, the attribute not existing,
124 : * or a permissions failure are always reported at ERROR. Other errors, such
125 : * as a conversion failure on one statistic kind, are reported as a WARNING
126 : * and other statistic kinds may still be updated.
127 : */
128 : static bool
129 1438 : attribute_statistics_update(FunctionCallInfo fcinfo)
130 : {
131 : char *nspname;
132 : char *relname;
133 : Oid reloid;
134 : char *attname;
135 : AttrNumber attnum;
136 : bool inherited;
137 1438 : Oid locked_table = InvalidOid;
138 :
139 : Relation starel;
140 : HeapTuple statup;
141 :
142 1438 : Oid atttypid = InvalidOid;
143 : int32 atttypmod;
144 : char atttyptype;
145 1438 : Oid atttypcoll = InvalidOid;
146 1438 : Oid eq_opr = InvalidOid;
147 1438 : Oid lt_opr = InvalidOid;
148 :
149 1438 : Oid elemtypid = InvalidOid;
150 1438 : Oid elem_eq_opr = InvalidOid;
151 :
152 : FmgrInfo array_in_fn;
153 :
154 2090 : bool do_mcv = !PG_ARGISNULL(MOST_COMMON_FREQS_ARG) &&
155 652 : !PG_ARGISNULL(MOST_COMMON_VALS_ARG);
156 1438 : bool do_histogram = !PG_ARGISNULL(HISTOGRAM_BOUNDS_ARG);
157 1438 : bool do_correlation = !PG_ARGISNULL(CORRELATION_ARG);
158 1484 : bool do_mcelem = !PG_ARGISNULL(MOST_COMMON_ELEMS_ARG) &&
159 46 : !PG_ARGISNULL(MOST_COMMON_ELEM_FREQS_ARG);
160 1438 : bool do_dechist = !PG_ARGISNULL(ELEM_COUNT_HISTOGRAM_ARG);
161 1438 : bool do_bounds_histogram = !PG_ARGISNULL(RANGE_BOUNDS_HISTOGRAM_ARG);
162 1468 : bool do_range_length_histogram = !PG_ARGISNULL(RANGE_LENGTH_HISTOGRAM_ARG) &&
163 30 : !PG_ARGISNULL(RANGE_EMPTY_FRAC_ARG);
164 :
165 1438 : Datum values[Natts_pg_statistic] = {0};
166 1438 : bool nulls[Natts_pg_statistic] = {0};
167 1438 : bool replaces[Natts_pg_statistic] = {0};
168 :
169 1438 : bool result = true;
170 :
171 1438 : stats_check_required_arg(fcinfo, attarginfo, ATTRELSCHEMA_ARG);
172 1432 : stats_check_required_arg(fcinfo, attarginfo, ATTRELNAME_ARG);
173 :
174 1420 : nspname = TextDatumGetCString(PG_GETARG_DATUM(ATTRELSCHEMA_ARG));
175 1420 : relname = TextDatumGetCString(PG_GETARG_DATUM(ATTRELNAME_ARG));
176 :
177 1420 : if (RecoveryInProgress())
178 0 : ereport(ERROR,
179 : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
180 : errmsg("recovery is in progress"),
181 : errhint("Statistics cannot be modified during recovery.")));
182 :
183 : /* lock before looking up attribute */
184 1420 : reloid = RangeVarGetRelidExtended(makeRangeVar(nspname, relname, -1),
185 : ShareUpdateExclusiveLock, 0,
186 : RangeVarCallbackForStats, &locked_table);
187 :
188 : /* user can specify either attname or attnum, but not both */
189 1408 : if (!PG_ARGISNULL(ATTNAME_ARG))
190 : {
191 1382 : if (!PG_ARGISNULL(ATTNUM_ARG))
192 6 : ereport(ERROR,
193 : (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
194 : errmsg("cannot specify both \"%s\" and \"%s\"", "attname", "attnum")));
195 1376 : attname = TextDatumGetCString(PG_GETARG_DATUM(ATTNAME_ARG));
196 1376 : attnum = get_attnum(reloid, attname);
197 : /* note that this test covers attisdropped cases too: */
198 1376 : if (attnum == InvalidAttrNumber)
199 6 : ereport(ERROR,
200 : (errcode(ERRCODE_UNDEFINED_COLUMN),
201 : errmsg("column \"%s\" of relation \"%s\" does not exist",
202 : attname, relname)));
203 : }
204 26 : else if (!PG_ARGISNULL(ATTNUM_ARG))
205 : {
206 14 : attnum = PG_GETARG_INT16(ATTNUM_ARG);
207 14 : attname = get_attname(reloid, attnum, true);
208 : /* annoyingly, get_attname doesn't check attisdropped */
209 14 : if (attname == NULL ||
210 14 : !SearchSysCacheExistsAttName(reloid, attname))
211 0 : ereport(ERROR,
212 : (errcode(ERRCODE_UNDEFINED_COLUMN),
213 : errmsg("column %d of relation \"%s\" does not exist",
214 : attnum, relname)));
215 : }
216 : else
217 : {
218 12 : ereport(ERROR,
219 : (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
220 : errmsg("must specify either \"%s\" or \"%s\"", "attname", "attnum")));
221 : attname = NULL; /* keep compiler quiet */
222 : attnum = 0;
223 : }
224 :
225 1384 : if (attnum < 0)
226 6 : ereport(ERROR,
227 : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
228 : errmsg("cannot modify statistics on system column \"%s\"",
229 : attname)));
230 :
231 1378 : stats_check_required_arg(fcinfo, attarginfo, INHERITED_ARG);
232 1372 : inherited = PG_GETARG_BOOL(INHERITED_ARG);
233 :
234 : /*
235 : * Check argument sanity. If some arguments are unusable, emit a WARNING
236 : * and set the corresponding argument to NULL in fcinfo.
237 : */
238 :
239 1372 : if (!stats_check_arg_array(fcinfo, attarginfo, MOST_COMMON_FREQS_ARG))
240 : {
241 0 : do_mcv = false;
242 0 : result = false;
243 : }
244 :
245 1372 : if (!stats_check_arg_array(fcinfo, attarginfo, MOST_COMMON_ELEM_FREQS_ARG))
246 : {
247 0 : do_mcelem = false;
248 0 : result = false;
249 : }
250 1372 : if (!stats_check_arg_array(fcinfo, attarginfo, ELEM_COUNT_HISTOGRAM_ARG))
251 : {
252 6 : do_dechist = false;
253 6 : result = false;
254 : }
255 :
256 1372 : if (!stats_check_arg_pair(fcinfo, attarginfo,
257 : MOST_COMMON_VALS_ARG, MOST_COMMON_FREQS_ARG))
258 : {
259 18 : do_mcv = false;
260 18 : result = false;
261 : }
262 :
263 1372 : if (!stats_check_arg_pair(fcinfo, attarginfo,
264 : MOST_COMMON_ELEMS_ARG,
265 : MOST_COMMON_ELEM_FREQS_ARG))
266 : {
267 12 : do_mcelem = false;
268 12 : result = false;
269 : }
270 :
271 1372 : if (!stats_check_arg_pair(fcinfo, attarginfo,
272 : RANGE_LENGTH_HISTOGRAM_ARG,
273 : RANGE_EMPTY_FRAC_ARG))
274 : {
275 12 : do_range_length_histogram = false;
276 12 : result = false;
277 : }
278 :
279 : /* derive information from attribute */
280 1372 : statatt_get_type(reloid, attnum,
281 : &atttypid, &atttypmod,
282 : &atttyptype, &atttypcoll,
283 : &eq_opr, <_opr);
284 :
285 : /* if needed, derive element type */
286 1372 : if (do_mcelem || do_dechist)
287 : {
288 52 : if (!statatt_get_elem_type(atttypid, atttyptype,
289 : &elemtypid, &elem_eq_opr))
290 : {
291 18 : ereport(WARNING,
292 : (errmsg("could not determine element type of column \"%s\"", attname),
293 : errdetail("Cannot set %s or %s.",
294 : "STATISTIC_KIND_MCELEM", "STATISTIC_KIND_DECHIST")));
295 18 : elemtypid = InvalidOid;
296 18 : elem_eq_opr = InvalidOid;
297 :
298 18 : do_mcelem = false;
299 18 : do_dechist = false;
300 18 : result = false;
301 : }
302 : }
303 :
304 : /* histogram and correlation require less-than operator */
305 1372 : if ((do_histogram || do_correlation) && !OidIsValid(lt_opr))
306 : {
307 0 : ereport(WARNING,
308 : (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
309 : errmsg("could not determine less-than operator for column \"%s\"", attname),
310 : errdetail("Cannot set %s or %s.",
311 : "STATISTIC_KIND_HISTOGRAM", "STATISTIC_KIND_CORRELATION")));
312 :
313 0 : do_histogram = false;
314 0 : do_correlation = false;
315 0 : result = false;
316 : }
317 :
318 : /* only range types can have range stats */
319 1372 : if ((do_range_length_histogram || do_bounds_histogram) &&
320 36 : !(atttyptype == TYPTYPE_RANGE || atttyptype == TYPTYPE_MULTIRANGE))
321 : {
322 12 : ereport(WARNING,
323 : (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
324 : errmsg("column \"%s\" is not a range type", attname),
325 : errdetail("Cannot set %s or %s.",
326 : "STATISTIC_KIND_RANGE_LENGTH_HISTOGRAM", "STATISTIC_KIND_BOUNDS_HISTOGRAM")));
327 :
328 12 : do_bounds_histogram = false;
329 12 : do_range_length_histogram = false;
330 12 : result = false;
331 : }
332 :
333 1372 : fmgr_info(F_ARRAY_IN, &array_in_fn);
334 :
335 1372 : starel = table_open(StatisticRelationId, RowExclusiveLock);
336 :
337 1372 : statup = SearchSysCache3(STATRELATTINH, ObjectIdGetDatum(reloid), Int16GetDatum(attnum), BoolGetDatum(inherited));
338 :
339 : /* initialize from existing tuple if exists */
340 1372 : if (HeapTupleIsValid(statup))
341 126 : heap_deform_tuple(statup, RelationGetDescr(starel), values, nulls);
342 : else
343 1246 : statatt_init_empty_tuple(reloid, attnum, inherited, values, nulls,
344 : replaces);
345 :
346 : /* if specified, set to argument values */
347 1372 : if (!PG_ARGISNULL(NULL_FRAC_ARG))
348 : {
349 1342 : values[Anum_pg_statistic_stanullfrac - 1] = PG_GETARG_DATUM(NULL_FRAC_ARG);
350 1342 : replaces[Anum_pg_statistic_stanullfrac - 1] = true;
351 : }
352 1372 : if (!PG_ARGISNULL(AVG_WIDTH_ARG))
353 : {
354 1228 : values[Anum_pg_statistic_stawidth - 1] = PG_GETARG_DATUM(AVG_WIDTH_ARG);
355 1228 : replaces[Anum_pg_statistic_stawidth - 1] = true;
356 : }
357 1372 : if (!PG_ARGISNULL(N_DISTINCT_ARG))
358 : {
359 1228 : values[Anum_pg_statistic_stadistinct - 1] = PG_GETARG_DATUM(N_DISTINCT_ARG);
360 1228 : replaces[Anum_pg_statistic_stadistinct - 1] = true;
361 : }
362 :
363 : /* STATISTIC_KIND_MCV */
364 1372 : if (do_mcv)
365 : {
366 : bool converted;
367 646 : Datum stanumbers = PG_GETARG_DATUM(MOST_COMMON_FREQS_ARG);
368 646 : Datum stavalues = statatt_build_stavalues("most_common_vals",
369 : &array_in_fn,
370 : PG_GETARG_DATUM(MOST_COMMON_VALS_ARG),
371 : atttypid, atttypmod,
372 : &converted);
373 :
374 646 : if (converted)
375 : {
376 640 : statatt_set_slot(values, nulls, replaces,
377 : STATISTIC_KIND_MCV,
378 : eq_opr, atttypcoll,
379 : stanumbers, false, stavalues, false);
380 : }
381 : else
382 6 : result = false;
383 : }
384 :
385 : /* STATISTIC_KIND_HISTOGRAM */
386 1372 : if (do_histogram)
387 : {
388 : Datum stavalues;
389 618 : bool converted = false;
390 :
391 618 : stavalues = statatt_build_stavalues("histogram_bounds",
392 : &array_in_fn,
393 : PG_GETARG_DATUM(HISTOGRAM_BOUNDS_ARG),
394 : atttypid, atttypmod,
395 : &converted);
396 :
397 618 : if (converted)
398 : {
399 612 : statatt_set_slot(values, nulls, replaces,
400 : STATISTIC_KIND_HISTOGRAM,
401 : lt_opr, atttypcoll,
402 : 0, true, stavalues, false);
403 : }
404 : else
405 6 : result = false;
406 : }
407 :
408 : /* STATISTIC_KIND_CORRELATION */
409 1372 : if (do_correlation)
410 : {
411 1154 : Datum elems[] = {PG_GETARG_DATUM(CORRELATION_ARG)};
412 1154 : ArrayType *arry = construct_array_builtin(elems, 1, FLOAT4OID);
413 1154 : Datum stanumbers = PointerGetDatum(arry);
414 :
415 1154 : statatt_set_slot(values, nulls, replaces,
416 : STATISTIC_KIND_CORRELATION,
417 : lt_opr, atttypcoll,
418 : stanumbers, false, 0, true);
419 : }
420 :
421 : /* STATISTIC_KIND_MCELEM */
422 1372 : if (do_mcelem)
423 : {
424 28 : Datum stanumbers = PG_GETARG_DATUM(MOST_COMMON_ELEM_FREQS_ARG);
425 28 : bool converted = false;
426 : Datum stavalues;
427 :
428 28 : stavalues = statatt_build_stavalues("most_common_elems",
429 : &array_in_fn,
430 : PG_GETARG_DATUM(MOST_COMMON_ELEMS_ARG),
431 : elemtypid, atttypmod,
432 : &converted);
433 :
434 28 : if (converted)
435 : {
436 28 : statatt_set_slot(values, nulls, replaces,
437 : STATISTIC_KIND_MCELEM,
438 : elem_eq_opr, atttypcoll,
439 : stanumbers, false, stavalues, false);
440 : }
441 : else
442 0 : result = false;
443 : }
444 :
445 : /* STATISTIC_KIND_DECHIST */
446 1372 : if (do_dechist)
447 : {
448 26 : Datum stanumbers = PG_GETARG_DATUM(ELEM_COUNT_HISTOGRAM_ARG);
449 :
450 26 : statatt_set_slot(values, nulls, replaces,
451 : STATISTIC_KIND_DECHIST,
452 : elem_eq_opr, atttypcoll,
453 : stanumbers, false, 0, true);
454 : }
455 :
456 : /*
457 : * STATISTIC_KIND_BOUNDS_HISTOGRAM
458 : *
459 : * This stakind appears before STATISTIC_KIND_RANGE_LENGTH_HISTOGRAM even
460 : * though it is numerically greater, and all other stakinds appear in
461 : * numerical order. We duplicate this quirk for consistency.
462 : */
463 1372 : if (do_bounds_histogram)
464 : {
465 18 : bool converted = false;
466 : Datum stavalues;
467 :
468 18 : stavalues = statatt_build_stavalues("range_bounds_histogram",
469 : &array_in_fn,
470 : PG_GETARG_DATUM(RANGE_BOUNDS_HISTOGRAM_ARG),
471 : atttypid, atttypmod,
472 : &converted);
473 :
474 18 : if (converted)
475 : {
476 18 : statatt_set_slot(values, nulls, replaces,
477 : STATISTIC_KIND_BOUNDS_HISTOGRAM,
478 : InvalidOid, InvalidOid,
479 : 0, true, stavalues, false);
480 : }
481 : else
482 0 : result = false;
483 : }
484 :
485 : /* STATISTIC_KIND_RANGE_LENGTH_HISTOGRAM */
486 1372 : if (do_range_length_histogram)
487 : {
488 : /* The anyarray is always a float8[] for this stakind */
489 18 : Datum elems[] = {PG_GETARG_DATUM(RANGE_EMPTY_FRAC_ARG)};
490 18 : ArrayType *arry = construct_array_builtin(elems, 1, FLOAT4OID);
491 18 : Datum stanumbers = PointerGetDatum(arry);
492 :
493 18 : bool converted = false;
494 : Datum stavalues;
495 :
496 18 : stavalues = statatt_build_stavalues("range_length_histogram",
497 : &array_in_fn,
498 : PG_GETARG_DATUM(RANGE_LENGTH_HISTOGRAM_ARG),
499 : FLOAT8OID, 0, &converted);
500 :
501 18 : if (converted)
502 : {
503 18 : statatt_set_slot(values, nulls, replaces,
504 : STATISTIC_KIND_RANGE_LENGTH_HISTOGRAM,
505 : Float8LessOperator, InvalidOid,
506 : stanumbers, false, stavalues, false);
507 : }
508 : else
509 0 : result = false;
510 : }
511 :
512 1372 : upsert_pg_statistic(starel, statup, values, nulls, replaces);
513 :
514 1372 : if (HeapTupleIsValid(statup))
515 126 : ReleaseSysCache(statup);
516 1372 : table_close(starel, RowExclusiveLock);
517 :
518 1372 : return result;
519 : }
520 :
521 : /*
522 : * Upsert the pg_statistic record.
523 : */
524 : static void
525 1372 : upsert_pg_statistic(Relation starel, HeapTuple oldtup,
526 : const Datum *values, const bool *nulls, const bool *replaces)
527 : {
528 : HeapTuple newtup;
529 :
530 1372 : if (HeapTupleIsValid(oldtup))
531 : {
532 126 : newtup = heap_modify_tuple(oldtup, RelationGetDescr(starel),
533 : values, nulls, replaces);
534 126 : CatalogTupleUpdate(starel, &newtup->t_self, newtup);
535 : }
536 : else
537 : {
538 1246 : newtup = heap_form_tuple(RelationGetDescr(starel), values, nulls);
539 1246 : CatalogTupleInsert(starel, newtup);
540 : }
541 :
542 1372 : heap_freetuple(newtup);
543 :
544 1372 : CommandCounterIncrement();
545 1372 : }
546 :
547 : /*
548 : * Delete pg_statistic record.
549 : */
550 : static bool
551 6 : delete_pg_statistic(Oid reloid, AttrNumber attnum, bool stainherit)
552 : {
553 6 : Relation sd = table_open(StatisticRelationId, RowExclusiveLock);
554 : HeapTuple oldtup;
555 6 : bool result = false;
556 :
557 : /* Is there already a pg_statistic tuple for this attribute? */
558 6 : oldtup = SearchSysCache3(STATRELATTINH,
559 : ObjectIdGetDatum(reloid),
560 : Int16GetDatum(attnum),
561 : BoolGetDatum(stainherit));
562 :
563 6 : if (HeapTupleIsValid(oldtup))
564 : {
565 6 : CatalogTupleDelete(sd, &oldtup->t_self);
566 6 : ReleaseSysCache(oldtup);
567 6 : result = true;
568 : }
569 :
570 6 : table_close(sd, RowExclusiveLock);
571 :
572 6 : CommandCounterIncrement();
573 :
574 6 : return result;
575 : }
576 :
577 : /*
578 : * Delete statistics for the given attribute.
579 : */
580 : Datum
581 6 : pg_clear_attribute_stats(PG_FUNCTION_ARGS)
582 : {
583 : char *nspname;
584 : char *relname;
585 : Oid reloid;
586 : char *attname;
587 : AttrNumber attnum;
588 : bool inherited;
589 6 : Oid locked_table = InvalidOid;
590 :
591 6 : stats_check_required_arg(fcinfo, cleararginfo, C_ATTRELSCHEMA_ARG);
592 6 : stats_check_required_arg(fcinfo, cleararginfo, C_ATTRELNAME_ARG);
593 6 : stats_check_required_arg(fcinfo, cleararginfo, C_ATTNAME_ARG);
594 6 : stats_check_required_arg(fcinfo, cleararginfo, C_INHERITED_ARG);
595 :
596 6 : nspname = TextDatumGetCString(PG_GETARG_DATUM(C_ATTRELSCHEMA_ARG));
597 6 : relname = TextDatumGetCString(PG_GETARG_DATUM(C_ATTRELNAME_ARG));
598 :
599 6 : if (RecoveryInProgress())
600 0 : ereport(ERROR,
601 : (errcode(ERRCODE_OBJECT_NOT_IN_PREREQUISITE_STATE),
602 : errmsg("recovery is in progress"),
603 : errhint("Statistics cannot be modified during recovery.")));
604 :
605 6 : reloid = RangeVarGetRelidExtended(makeRangeVar(nspname, relname, -1),
606 : ShareUpdateExclusiveLock, 0,
607 : RangeVarCallbackForStats, &locked_table);
608 :
609 6 : attname = TextDatumGetCString(PG_GETARG_DATUM(C_ATTNAME_ARG));
610 6 : attnum = get_attnum(reloid, attname);
611 :
612 6 : if (attnum < 0)
613 0 : ereport(ERROR,
614 : (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
615 : errmsg("cannot clear statistics on system column \"%s\"",
616 : attname)));
617 :
618 6 : if (attnum == InvalidAttrNumber)
619 0 : ereport(ERROR,
620 : (errcode(ERRCODE_UNDEFINED_COLUMN),
621 : errmsg("column \"%s\" of relation \"%s\" does not exist",
622 : attname, get_rel_name(reloid))));
623 :
624 6 : inherited = PG_GETARG_BOOL(C_INHERITED_ARG);
625 :
626 6 : delete_pg_statistic(reloid, attnum, inherited);
627 6 : PG_RETURN_VOID();
628 : }
629 :
630 : /*
631 : * Import statistics for a given relation attribute.
632 : *
633 : * Inserts or replaces a row in pg_statistic for the given relation and
634 : * attribute name or number. It takes input parameters that correspond to
635 : * columns in the view pg_stats.
636 : *
637 : * Parameters are given in a pseudo named-attribute style: they must be
638 : * pairs of parameter names (as text) and values (of appropriate types).
639 : * We do that, rather than using regular named-parameter notation, so
640 : * that we can add or change parameters without fear of breaking
641 : * carelessly-written calls.
642 : *
643 : * Parameters null_frac, avg_width, and n_distinct all correspond to NOT NULL
644 : * columns in pg_statistic. The remaining parameters all belong to a specific
645 : * stakind. Some stakinds require multiple parameters, which must be specified
646 : * together (or neither specified).
647 : *
648 : * Parameters are only superficially validated. Omitting a parameter or
649 : * passing NULL leaves the statistic unchanged.
650 : *
651 : * Parameters corresponding to ANYARRAY columns are instead passed in as text
652 : * values, which is a valid input string for an array of the type or element
653 : * type of the attribute. Any error generated by the array_in() function will
654 : * in turn fail the function.
655 : */
656 : Datum
657 1438 : pg_restore_attribute_stats(PG_FUNCTION_ARGS)
658 : {
659 1438 : LOCAL_FCINFO(positional_fcinfo, NUM_ATTRIBUTE_STATS_ARGS);
660 1438 : bool result = true;
661 :
662 1438 : InitFunctionCallInfoData(*positional_fcinfo, NULL, NUM_ATTRIBUTE_STATS_ARGS,
663 : InvalidOid, NULL, NULL);
664 :
665 1438 : if (!stats_fill_fcinfo_from_arg_pairs(fcinfo, positional_fcinfo,
666 : attarginfo))
667 12 : result = false;
668 :
669 1438 : if (!attribute_statistics_update(positional_fcinfo))
670 90 : result = false;
671 :
672 1372 : PG_RETURN_BOOL(result);
673 : }
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