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execGrouping.c
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1 /*-------------------------------------------------------------------------
2  *
3  * execGrouping.c
4  * executor utility routines for grouping, hashing, and aggregation
5  *
6  * Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
7  * Portions Copyright (c) 1994, Regents of the University of California
8  *
9  *
10  * IDENTIFICATION
11  * src/backend/executor/execGrouping.c
12  *
13  *-------------------------------------------------------------------------
14  */
15 #include "postgres.h"
16 
17 #include "access/parallel.h"
18 #include "common/hashfn.h"
19 #include "executor/executor.h"
20 #include "miscadmin.h"
21 #include "utils/lsyscache.h"
22 #include "utils/memutils.h"
23 
24 static int TupleHashTableMatch(struct tuplehash_hash *tb, const MinimalTuple tuple1, const MinimalTuple tuple2);
25 static inline uint32 TupleHashTableHash_internal(struct tuplehash_hash *tb,
26  const MinimalTuple tuple);
28  TupleTableSlot *slot,
29  bool *isnew, uint32 hash);
30 
31 /*
32  * Define parameters for tuple hash table code generation. The interface is
33  * *also* declared in execnodes.h (to generate the types, which are externally
34  * visible).
35  */
36 #define SH_PREFIX tuplehash
37 #define SH_ELEMENT_TYPE TupleHashEntryData
38 #define SH_KEY_TYPE MinimalTuple
39 #define SH_KEY firstTuple
40 #define SH_HASH_KEY(tb, key) TupleHashTableHash_internal(tb, key)
41 #define SH_EQUAL(tb, a, b) TupleHashTableMatch(tb, a, b) == 0
42 #define SH_SCOPE extern
43 #define SH_STORE_HASH
44 #define SH_GET_HASH(tb, a) a->hash
45 #define SH_DEFINE
46 #include "lib/simplehash.h"
47 
48 
49 /*****************************************************************************
50  * Utility routines for grouping tuples together
51  *****************************************************************************/
52 
53 /*
54  * execTuplesMatchPrepare
55  * Build expression that can be evaluated using ExecQual(), returning
56  * whether an ExprContext's inner/outer tuples are NOT DISTINCT
57  */
58 ExprState *
60  int numCols,
61  const AttrNumber *keyColIdx,
62  const Oid *eqOperators,
63  const Oid *collations,
64  PlanState *parent)
65 {
66  Oid *eqFunctions = (Oid *) palloc(numCols * sizeof(Oid));
67  int i;
68  ExprState *expr;
69 
70  if (numCols == 0)
71  return NULL;
72 
73  /* lookup equality functions */
74  for (i = 0; i < numCols; i++)
75  eqFunctions[i] = get_opcode(eqOperators[i]);
76 
77  /* build actual expression */
78  expr = ExecBuildGroupingEqual(desc, desc, NULL, NULL,
79  numCols, keyColIdx, eqFunctions, collations,
80  parent);
81 
82  return expr;
83 }
84 
85 /*
86  * execTuplesHashPrepare
87  * Look up the equality and hashing functions needed for a TupleHashTable.
88  *
89  * This is similar to execTuplesMatchPrepare, but we also need to find the
90  * hash functions associated with the equality operators. *eqFunctions and
91  * *hashFunctions receive the palloc'd result arrays.
92  *
93  * Note: we expect that the given operators are not cross-type comparisons.
94  */
95 void
97  const Oid *eqOperators,
98  Oid **eqFuncOids,
99  FmgrInfo **hashFunctions)
100 {
101  int i;
102 
103  *eqFuncOids = (Oid *) palloc(numCols * sizeof(Oid));
104  *hashFunctions = (FmgrInfo *) palloc(numCols * sizeof(FmgrInfo));
105 
106  for (i = 0; i < numCols; i++)
107  {
108  Oid eq_opr = eqOperators[i];
109  Oid eq_function;
110  Oid left_hash_function;
111  Oid right_hash_function;
112 
113  eq_function = get_opcode(eq_opr);
114  if (!get_op_hash_functions(eq_opr,
115  &left_hash_function, &right_hash_function))
116  elog(ERROR, "could not find hash function for hash operator %u",
117  eq_opr);
118  /* We're not supporting cross-type cases here */
119  Assert(left_hash_function == right_hash_function);
120  (*eqFuncOids)[i] = eq_function;
121  fmgr_info(right_hash_function, &(*hashFunctions)[i]);
122  }
123 }
124 
125 
126 /*****************************************************************************
127  * Utility routines for all-in-memory hash tables
128  *
129  * These routines build hash tables for grouping tuples together (eg, for
130  * hash aggregation). There is one entry for each not-distinct set of tuples
131  * presented.
132  *****************************************************************************/
133 
134 /*
135  * Construct an empty TupleHashTable
136  *
137  * numCols, keyColIdx: identify the tuple fields to use as lookup key
138  * eqfunctions: equality comparison functions to use
139  * hashfunctions: datatype-specific hashing functions to use
140  * nbuckets: initial estimate of hashtable size
141  * additionalsize: size of data stored in ->additional
142  * metacxt: memory context for long-lived allocation, but not per-entry data
143  * tablecxt: memory context in which to store table entries
144  * tempcxt: short-lived context for evaluation hash and comparison functions
145  *
146  * The function arrays may be made with execTuplesHashPrepare(). Note they
147  * are not cross-type functions, but expect to see the table datatype(s)
148  * on both sides.
149  *
150  * Note that keyColIdx, eqfunctions, and hashfunctions must be allocated in
151  * storage that will live as long as the hashtable does.
152  */
155  TupleDesc inputDesc,
156  int numCols, AttrNumber *keyColIdx,
157  const Oid *eqfuncoids,
158  FmgrInfo *hashfunctions,
159  Oid *collations,
160  long nbuckets, Size additionalsize,
161  MemoryContext metacxt,
162  MemoryContext tablecxt,
163  MemoryContext tempcxt,
164  bool use_variable_hash_iv)
165 {
166  TupleHashTable hashtable;
167  Size entrysize = sizeof(TupleHashEntryData) + additionalsize;
168  int hash_mem = get_hash_mem();
169  MemoryContext oldcontext;
170  bool allow_jit;
171 
172  Assert(nbuckets > 0);
173 
174  /* Limit initial table size request to not more than hash_mem */
175  nbuckets = Min(nbuckets, (long) ((hash_mem * 1024L) / entrysize));
176 
177  oldcontext = MemoryContextSwitchTo(metacxt);
178 
179  hashtable = (TupleHashTable) palloc(sizeof(TupleHashTableData));
180 
181  hashtable->numCols = numCols;
182  hashtable->keyColIdx = keyColIdx;
183  hashtable->tab_hash_funcs = hashfunctions;
184  hashtable->tab_collations = collations;
185  hashtable->tablecxt = tablecxt;
186  hashtable->tempcxt = tempcxt;
187  hashtable->entrysize = entrysize;
188  hashtable->tableslot = NULL; /* will be made on first lookup */
189  hashtable->inputslot = NULL;
190  hashtable->in_hash_funcs = NULL;
191  hashtable->cur_eq_func = NULL;
192 
193  /*
194  * If parallelism is in use, even if the leader backend is performing the
195  * scan itself, we don't want to create the hashtable exactly the same way
196  * in all workers. As hashtables are iterated over in keyspace-order,
197  * doing so in all processes in the same way is likely to lead to
198  * "unbalanced" hashtables when the table size initially is
199  * underestimated.
200  */
201  if (use_variable_hash_iv)
203  else
204  hashtable->hash_iv = 0;
205 
206  hashtable->hashtab = tuplehash_create(metacxt, nbuckets, hashtable);
207 
208  /*
209  * We copy the input tuple descriptor just for safety --- we assume all
210  * input tuples will have equivalent descriptors.
211  */
214 
215  /*
216  * If the old reset interface is used (i.e. BuildTupleHashTable, rather
217  * than BuildTupleHashTableExt), allowing JIT would lead to the generated
218  * functions to a) live longer than the query b) be re-generated each time
219  * the table is being reset. Therefore prevent JIT from being used in that
220  * case, by not providing a parent node (which prevents accessing the
221  * JitContext in the EState).
222  */
223  allow_jit = metacxt != tablecxt;
224 
225  /* build comparator for all columns */
226  /* XXX: should we support non-minimal tuples for the inputslot? */
227  hashtable->tab_eq_func = ExecBuildGroupingEqual(inputDesc, inputDesc,
229  numCols,
230  keyColIdx, eqfuncoids, collations,
231  allow_jit ? parent : NULL);
232 
233  /*
234  * While not pretty, it's ok to not shut down this context, but instead
235  * rely on the containing memory context being reset, as
236  * ExecBuildGroupingEqual() only builds a very simple expression calling
237  * functions (i.e. nothing that'd employ RegisterExprContextCallback()).
238  */
240 
241  MemoryContextSwitchTo(oldcontext);
242 
243  return hashtable;
244 }
245 
246 /*
247  * BuildTupleHashTable is a backwards-compatibilty wrapper for
248  * BuildTupleHashTableExt(), that allocates the hashtable's metadata in
249  * tablecxt. Note that hashtables created this way cannot be reset leak-free
250  * with ResetTupleHashTable().
251  */
254  TupleDesc inputDesc,
255  int numCols, AttrNumber *keyColIdx,
256  const Oid *eqfuncoids,
257  FmgrInfo *hashfunctions,
258  Oid *collations,
259  long nbuckets, Size additionalsize,
260  MemoryContext tablecxt,
261  MemoryContext tempcxt,
262  bool use_variable_hash_iv)
263 {
264  return BuildTupleHashTableExt(parent,
265  inputDesc,
266  numCols, keyColIdx,
267  eqfuncoids,
268  hashfunctions,
269  collations,
270  nbuckets, additionalsize,
271  tablecxt,
272  tablecxt,
273  tempcxt,
274  use_variable_hash_iv);
275 }
276 
277 /*
278  * Reset contents of the hashtable to be empty, preserving all the non-content
279  * state. Note that the tablecxt passed to BuildTupleHashTableExt() should
280  * also be reset, otherwise there will be leaks.
281  */
282 void
284 {
285  tuplehash_reset(hashtable->hashtab);
286 }
287 
288 /*
289  * Find or create a hashtable entry for the tuple group containing the
290  * given tuple. The tuple must be the same type as the hashtable entries.
291  *
292  * If isnew is NULL, we do not create new entries; we return NULL if no
293  * match is found.
294  *
295  * If hash is not NULL, we set it to the calculated hash value. This allows
296  * callers access to the hash value even if no entry is returned.
297  *
298  * If isnew isn't NULL, then a new entry is created if no existing entry
299  * matches. On return, *isnew is true if the entry is newly created,
300  * false if it existed already. ->additional_data in the new entry has
301  * been zeroed.
302  */
305  bool *isnew, uint32 *hash)
306 {
307  TupleHashEntry entry;
308  MemoryContext oldContext;
309  uint32 local_hash;
310 
311  /* Need to run the hash functions in short-lived context */
312  oldContext = MemoryContextSwitchTo(hashtable->tempcxt);
313 
314  /* set up data needed by hash and match functions */
315  hashtable->inputslot = slot;
316  hashtable->in_hash_funcs = hashtable->tab_hash_funcs;
317  hashtable->cur_eq_func = hashtable->tab_eq_func;
318 
319  local_hash = TupleHashTableHash_internal(hashtable->hashtab, NULL);
320  entry = LookupTupleHashEntry_internal(hashtable, slot, isnew, local_hash);
321 
322  if (hash != NULL)
323  *hash = local_hash;
324 
325  Assert(entry == NULL || entry->hash == local_hash);
326 
327  MemoryContextSwitchTo(oldContext);
328 
329  return entry;
330 }
331 
332 /*
333  * Compute the hash value for a tuple
334  */
335 uint32
337 {
338  MemoryContext oldContext;
339  uint32 hash;
340 
341  hashtable->inputslot = slot;
342  hashtable->in_hash_funcs = hashtable->tab_hash_funcs;
343 
344  /* Need to run the hash functions in short-lived context */
345  oldContext = MemoryContextSwitchTo(hashtable->tempcxt);
346 
347  hash = TupleHashTableHash_internal(hashtable->hashtab, NULL);
348 
349  MemoryContextSwitchTo(oldContext);
350 
351  return hash;
352 }
353 
354 /*
355  * A variant of LookupTupleHashEntry for callers that have already computed
356  * the hash value.
357  */
360  bool *isnew, uint32 hash)
361 {
362  TupleHashEntry entry;
363  MemoryContext oldContext;
364 
365  /* Need to run the hash functions in short-lived context */
366  oldContext = MemoryContextSwitchTo(hashtable->tempcxt);
367 
368  /* set up data needed by hash and match functions */
369  hashtable->inputslot = slot;
370  hashtable->in_hash_funcs = hashtable->tab_hash_funcs;
371  hashtable->cur_eq_func = hashtable->tab_eq_func;
372 
373  entry = LookupTupleHashEntry_internal(hashtable, slot, isnew, hash);
374  Assert(entry == NULL || entry->hash == hash);
375 
376  MemoryContextSwitchTo(oldContext);
377 
378  return entry;
379 }
380 
381 /*
382  * Search for a hashtable entry matching the given tuple. No entry is
383  * created if there's not a match. This is similar to the non-creating
384  * case of LookupTupleHashEntry, except that it supports cross-type
385  * comparisons, in which the given tuple is not of the same type as the
386  * table entries. The caller must provide the hash functions to use for
387  * the input tuple, as well as the equality functions, since these may be
388  * different from the table's internal functions.
389  */
392  ExprState *eqcomp,
393  FmgrInfo *hashfunctions)
394 {
395  TupleHashEntry entry;
396  MemoryContext oldContext;
398 
399  /* Need to run the hash functions in short-lived context */
400  oldContext = MemoryContextSwitchTo(hashtable->tempcxt);
401 
402  /* Set up data needed by hash and match functions */
403  hashtable->inputslot = slot;
404  hashtable->in_hash_funcs = hashfunctions;
405  hashtable->cur_eq_func = eqcomp;
406 
407  /* Search the hash table */
408  key = NULL; /* flag to reference inputslot */
409  entry = tuplehash_lookup(hashtable->hashtab, key);
410  MemoryContextSwitchTo(oldContext);
411 
412  return entry;
413 }
414 
415 /*
416  * If tuple is NULL, use the input slot instead. This convention avoids the
417  * need to materialize virtual input tuples unless they actually need to get
418  * copied into the table.
419  *
420  * Also, the caller must select an appropriate memory context for running
421  * the hash functions. (dynahash.c doesn't change CurrentMemoryContext.)
422  */
423 static uint32
424 TupleHashTableHash_internal(struct tuplehash_hash *tb,
425  const MinimalTuple tuple)
426 {
427  TupleHashTable hashtable = (TupleHashTable) tb->private_data;
428  int numCols = hashtable->numCols;
429  AttrNumber *keyColIdx = hashtable->keyColIdx;
430  uint32 hashkey = hashtable->hash_iv;
431  TupleTableSlot *slot;
432  FmgrInfo *hashfunctions;
433  int i;
434 
435  if (tuple == NULL)
436  {
437  /* Process the current input tuple for the table */
438  slot = hashtable->inputslot;
439  hashfunctions = hashtable->in_hash_funcs;
440  }
441  else
442  {
443  /*
444  * Process a tuple already stored in the table.
445  *
446  * (this case never actually occurs due to the way simplehash.h is
447  * used, as the hash-value is stored in the entries)
448  */
449  slot = hashtable->tableslot;
450  ExecStoreMinimalTuple(tuple, slot, false);
451  hashfunctions = hashtable->tab_hash_funcs;
452  }
453 
454  for (i = 0; i < numCols; i++)
455  {
456  AttrNumber att = keyColIdx[i];
457  Datum attr;
458  bool isNull;
459 
460  /* rotate hashkey left 1 bit at each step */
461  hashkey = (hashkey << 1) | ((hashkey & 0x80000000) ? 1 : 0);
462 
463  attr = slot_getattr(slot, att, &isNull);
464 
465  if (!isNull) /* treat nulls as having hash key 0 */
466  {
467  uint32 hkey;
468 
469  hkey = DatumGetUInt32(FunctionCall1Coll(&hashfunctions[i],
470  hashtable->tab_collations[i],
471  attr));
472  hashkey ^= hkey;
473  }
474  }
475 
476  /*
477  * The way hashes are combined above, among each other and with the IV,
478  * doesn't lead to good bit perturbation. As the IV's goal is to lead to
479  * achieve that, perform a round of hashing of the combined hash -
480  * resulting in near perfect perturbation.
481  */
482  return murmurhash32(hashkey);
483 }
484 
485 /*
486  * Does the work of LookupTupleHashEntry and LookupTupleHashEntryHash. Useful
487  * so that we can avoid switching the memory context multiple times for
488  * LookupTupleHashEntry.
489  *
490  * NB: This function may or may not change the memory context. Caller is
491  * expected to change it back.
492  */
493 static inline TupleHashEntry
495  bool *isnew, uint32 hash)
496 {
497  TupleHashEntryData *entry;
498  bool found;
500 
501  key = NULL; /* flag to reference inputslot */
502 
503  if (isnew)
504  {
505  entry = tuplehash_insert_hash(hashtable->hashtab, key, hash, &found);
506 
507  if (found)
508  {
509  /* found pre-existing entry */
510  *isnew = false;
511  }
512  else
513  {
514  /* created new entry */
515  *isnew = true;
516  /* zero caller data */
517  entry->additional = NULL;
518  MemoryContextSwitchTo(hashtable->tablecxt);
519  /* Copy the first tuple into the table context */
520  entry->firstTuple = ExecCopySlotMinimalTuple(slot);
521  }
522  }
523  else
524  {
525  entry = tuplehash_lookup_hash(hashtable->hashtab, key, hash);
526  }
527 
528  return entry;
529 }
530 
531 /*
532  * See whether two tuples (presumably of the same hash value) match
533  */
534 static int
535 TupleHashTableMatch(struct tuplehash_hash *tb, const MinimalTuple tuple1, const MinimalTuple tuple2)
536 {
537  TupleTableSlot *slot1;
538  TupleTableSlot *slot2;
539  TupleHashTable hashtable = (TupleHashTable) tb->private_data;
540  ExprContext *econtext = hashtable->exprcontext;
541 
542  /*
543  * We assume that simplehash.h will only ever call us with the first
544  * argument being an actual table entry, and the second argument being
545  * LookupTupleHashEntry's dummy TupleHashEntryData. The other direction
546  * could be supported too, but is not currently required.
547  */
548  Assert(tuple1 != NULL);
549  slot1 = hashtable->tableslot;
550  ExecStoreMinimalTuple(tuple1, slot1, false);
551  Assert(tuple2 == NULL);
552  slot2 = hashtable->inputslot;
553 
554  /* For crosstype comparisons, the inputslot must be first */
555  econtext->ecxt_innertuple = slot2;
556  econtext->ecxt_outertuple = slot1;
557  return !ExecQualAndReset(hashtable->cur_eq_func, econtext);
558 }
ExprContext * exprcontext
Definition: execnodes.h:717
#define DatumGetUInt32(X)
Definition: postgres.h:486
ExprContext * CreateStandaloneExprContext(void)
Definition: execUtils.c:351
Definition: fmgr.h:56
TupleHashTable BuildTupleHashTableExt(PlanState *parent, TupleDesc inputDesc, int numCols, AttrNumber *keyColIdx, const Oid *eqfuncoids, FmgrInfo *hashfunctions, Oid *collations, long nbuckets, Size additionalsize, MemoryContext metacxt, MemoryContext tablecxt, MemoryContext tempcxt, bool use_variable_hash_iv)
Definition: execGrouping.c:154
TupleDesc CreateTupleDescCopy(TupleDesc tupdesc)
Definition: tupdesc.c:110
bool get_op_hash_functions(Oid opno, RegProcedure *lhs_procno, RegProcedure *rhs_procno)
Definition: lsyscache.c:508
TupleHashEntry LookupTupleHashEntryHash(TupleHashTable hashtable, TupleTableSlot *slot, bool *isnew, uint32 hash)
Definition: execGrouping.c:359
TupleTableSlot * ExecStoreMinimalTuple(MinimalTuple mtup, TupleTableSlot *slot, bool shouldFree)
Definition: execTuples.c:1416
TupleTableSlot * MakeSingleTupleTableSlot(TupleDesc tupdesc, const TupleTableSlotOps *tts_ops)
Definition: execTuples.c:1208
ExprState * ExecBuildGroupingEqual(TupleDesc ldesc, TupleDesc rdesc, const TupleTableSlotOps *lops, const TupleTableSlotOps *rops, int numCols, const AttrNumber *keyColIdx, const Oid *eqfunctions, const Oid *collations, PlanState *parent)
Definition: execExpr.c:3333
TupleTableSlot * inputslot
Definition: execnodes.h:713
MinimalTuple firstTuple
Definition: execnodes.h:686
static uint32 TupleHashTableHash_internal(struct tuplehash_hash *tb, const MinimalTuple tuple)
Definition: execGrouping.c:424
#define Min(x, y)
Definition: c.h:928
TupleHashEntry FindTupleHashEntry(TupleHashTable hashtable, TupleTableSlot *slot, ExprState *eqcomp, FmgrInfo *hashfunctions)
Definition: execGrouping.c:391
static MemoryContext MemoryContextSwitchTo(MemoryContext context)
Definition: palloc.h:109
AttrNumber * keyColIdx
Definition: execnodes.h:704
ExprState * tab_eq_func
Definition: execnodes.h:706
ExprState * cur_eq_func
Definition: execnodes.h:715
static uint32 murmurhash32(uint32 data)
Definition: hashfn.h:92
unsigned int Oid
Definition: postgres_ext.h:31
TupleHashEntry LookupTupleHashEntry(TupleHashTable hashtable, TupleTableSlot *slot, bool *isnew, uint32 *hash)
Definition: execGrouping.c:304
void execTuplesHashPrepare(int numCols, const Oid *eqOperators, Oid **eqFuncOids, FmgrInfo **hashFunctions)
Definition: execGrouping.c:96
void ResetTupleHashTable(TupleHashTable hashtable)
Definition: execGrouping.c:283
FmgrInfo * tab_hash_funcs
Definition: execnodes.h:705
static int TupleHashTableMatch(struct tuplehash_hash *tb, const MinimalTuple tuple1, const MinimalTuple tuple2)
Definition: execGrouping.c:535
FmgrInfo * in_hash_funcs
Definition: execnodes.h:714
#define ERROR
Definition: elog.h:43
void fmgr_info(Oid functionId, FmgrInfo *finfo)
Definition: fmgr.c:126
struct TupleHashEntryData TupleHashEntryData
static TupleHashEntry LookupTupleHashEntry_internal(TupleHashTable hashtable, TupleTableSlot *slot, bool *isnew, uint32 hash)
Definition: execGrouping.c:494
static MinimalTuple ExecCopySlotMinimalTuple(TupleTableSlot *slot)
Definition: tuptable.h:463
MemoryContext tablecxt
Definition: execnodes.h:708
struct TupleHashTableData * TupleHashTable
Definition: execnodes.h:682
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Definition: parallel.c:112
unsigned int uint32
Definition: c.h:375
static bool ExecQualAndReset(ExprState *state, ExprContext *econtext)
Definition: executor.h:399
uintptr_t Datum
Definition: postgres.h:367
Datum FunctionCall1Coll(FmgrInfo *flinfo, Oid collation, Datum arg1)
Definition: fmgr.c:1132
TupleHashTable BuildTupleHashTable(PlanState *parent, TupleDesc inputDesc, int numCols, AttrNumber *keyColIdx, const Oid *eqfuncoids, FmgrInfo *hashfunctions, Oid *collations, long nbuckets, Size additionalsize, MemoryContext tablecxt, MemoryContext tempcxt, bool use_variable_hash_iv)
Definition: execGrouping.c:253
static Datum slot_getattr(TupleTableSlot *slot, int attnum, bool *isnull)
Definition: tuptable.h:381
RegProcedure get_opcode(Oid opno)
Definition: lsyscache.c:1202
tuplehash_hash * hashtab
Definition: execnodes.h:702
#define Assert(condition)
Definition: c.h:746
TupleTableSlot * tableslot
Definition: execnodes.h:711
ExprState * execTuplesMatchPrepare(TupleDesc desc, int numCols, const AttrNumber *keyColIdx, const Oid *eqOperators, const Oid *collations, PlanState *parent)
Definition: execGrouping.c:59
size_t Size
Definition: c.h:474
uint32 TupleHashTableHash(TupleHashTable hashtable, TupleTableSlot *slot)
Definition: execGrouping.c:336
void * palloc(Size size)
Definition: mcxt.c:950
#define elog(elevel,...)
Definition: elog.h:214
int i
MemoryContext tempcxt
Definition: execnodes.h:709
static unsigned hash(unsigned *uv, int n)
Definition: rege_dfa.c:541
int16 AttrNumber
Definition: attnum.h:21
const TupleTableSlotOps TTSOpsMinimalTuple
Definition: execTuples.c:85
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Definition: nodeHash.c:3389