#include "postgres.h"
#include "access/nbtree.h"
#include "access/relscan.h"
#include "access/tableam.h"
#include "catalog/pg_am.h"
#include "executor/executor.h"
#include "executor/nodeIndexscan.h"
#include "lib/pairingheap.h"
#include "miscadmin.h"
#include "nodes/nodeFuncs.h"
#include "utils/array.h"
#include "utils/datum.h"
#include "utils/lsyscache.h"
#include "utils/rel.h"

Include dependency graph for nodeIndexscan.c:

Data Structures
struct	ReorderTuple

Functions
static TupleTableSlot *	IndexNext (IndexScanState *node)

static TupleTableSlot *	IndexNextWithReorder (IndexScanState *node)

static void	EvalOrderByExpressions (IndexScanState node, ExprContext econtext)

static bool	IndexRecheck (IndexScanState node, TupleTableSlot slot)

static int	cmp_orderbyvals (const Datum adist, const bool anulls, const Datum bdist, const bool bnulls, IndexScanState *node)

static int	reorderqueue_cmp (const pairingheap_node a, const pairingheap_node b, void *arg)

static void	reorderqueue_push (IndexScanState node, TupleTableSlot slot, Datum orderbyvals, bool orderbynulls)

static HeapTuple	reorderqueue_pop (IndexScanState *node)

static TupleTableSlot *	ExecIndexScan (PlanState *pstate)

void	ExecReScanIndexScan (IndexScanState *node)

void	ExecIndexEvalRuntimeKeys (ExprContext econtext, IndexRuntimeKeyInfo runtimeKeys, int numRuntimeKeys)

bool	ExecIndexEvalArrayKeys (ExprContext econtext, IndexArrayKeyInfo arrayKeys, int numArrayKeys)

bool	ExecIndexAdvanceArrayKeys (IndexArrayKeyInfo *arrayKeys, int numArrayKeys)

void	ExecEndIndexScan (IndexScanState *node)

void	ExecIndexMarkPos (IndexScanState *node)

void	ExecIndexRestrPos (IndexScanState *node)

IndexScanState *	ExecInitIndexScan (IndexScan node, EState estate, int eflags)

void	ExecIndexBuildScanKeys (PlanState planstate, Relation index, List quals, bool isorderby, ScanKey scanKeys, int numScanKeys, IndexRuntimeKeyInfo *runtimeKeys, int numRuntimeKeys, IndexArrayKeyInfo *arrayKeys, int numArrayKeys)

void	ExecIndexScanEstimate (IndexScanState node, ParallelContext pcxt)

void	ExecIndexScanInitializeDSM (IndexScanState node, ParallelContext pcxt)

void	ExecIndexScanReInitializeDSM (IndexScanState node, ParallelContext pcxt)

void	ExecIndexScanInitializeWorker (IndexScanState node, ParallelWorkerContext pwcxt)

Function Documentation

◆ cmp_orderbyvals()

static int cmp_orderbyvals	(	const Datum *	adist,
		const bool *	anulls,
		const Datum *	bdist,
		const bool *	bnulls,
		IndexScanState *	node
	)

static

Definition at line 405 of file nodeIndexscan.c.

 {
     int         i;
     int         result;
  
     for (i = 0; i < node->iss_NumOrderByKeys; i++)
     {
         SortSupport ssup = &node->iss_SortSupport[i];
  
         /*
          * Handle nulls.  We only need to support NULLS LAST ordering, because
          * match_pathkeys_to_index() doesn't consider indexorderby
          * implementation otherwise.
          */
         if (anulls[i] && !bnulls[i])
             return 1;
         else if (!anulls[i] && bnulls[i])
             return -1;
         else if (anulls[i] && bnulls[i])
             return 0;
  
         result = ssup->comparator(adist[i], bdist[i], ssup);
         if (result != 0)
             return result;
     }
  
     return 0;
 }

References SortSupportData::comparator, i, IndexScanState::iss_NumOrderByKeys, and IndexScanState::iss_SortSupport.

Referenced by IndexNextWithReorder(), and reorderqueue_cmp().

◆ EvalOrderByExpressions()

static void EvalOrderByExpressions	(	IndexScanState *	node,
		ExprContext *	econtext
	)

static

Definition at line 360 of file nodeIndexscan.c.

 {
     int         i;
     ListCell   *l;
     MemoryContext oldContext;
  
     oldContext = MemoryContextSwitchTo(econtext->ecxt_per_tuple_memory);
  
     i = 0;
     foreach(l, node->indexorderbyorig)
     {
         ExprState  *orderby = (ExprState *) lfirst(l);
  
         node->iss_OrderByValues[i] = ExecEvalExpr(orderby,
                                                   econtext,
                                                   &node->iss_OrderByNulls[i]);
         i++;
     }
  
     MemoryContextSwitchTo(oldContext);
 }

References ExprContext::ecxt_per_tuple_memory, ExecEvalExpr(), i, IndexScanState::indexorderbyorig, IndexScanState::iss_OrderByNulls, IndexScanState::iss_OrderByValues, lfirst, and MemoryContextSwitchTo().

Referenced by IndexNextWithReorder().

◆ ExecEndIndexScan()

void ExecEndIndexScan ( IndexScanState * node )

Definition at line 785 of file nodeIndexscan.c.

 {
     Relation    indexRelationDesc;
     IndexScanDesc indexScanDesc;
  
     /*
      * extract information from the node
      */
     indexRelationDesc = node->iss_RelationDesc;
     indexScanDesc = node->iss_ScanDesc;
  
     /*
      * close the index relation (no-op if we didn't open it)
      */
     if (indexScanDesc)
         index_endscan(indexScanDesc);
     if (indexRelationDesc)
         index_close(indexRelationDesc, NoLock);
 }

References index_close(), index_endscan(), IndexScanState::iss_RelationDesc, IndexScanState::iss_ScanDesc, and NoLock.

Referenced by ExecEndNode().

◆ ExecIndexAdvanceArrayKeys()

bool ExecIndexAdvanceArrayKeys	(	IndexArrayKeyInfo *	arrayKeys,
		int	numArrayKeys
	)

Definition at line 740 of file nodeIndexscan.c.

 {
     bool        found = false;
     int         j;
  
     /*
      * Note we advance the rightmost array key most quickly, since it will
      * correspond to the lowest-order index column among the available
      * qualifications.  This is hypothesized to result in better locality of
      * access in the index.
      */
     for (j = numArrayKeys - 1; j >= 0; j--)
     {
         ScanKey     scan_key = arrayKeys[j].scan_key;
         int         next_elem = arrayKeys[j].next_elem;
         int         num_elems = arrayKeys[j].num_elems;
         Datum      *elem_values = arrayKeys[j].elem_values;
         bool       *elem_nulls = arrayKeys[j].elem_nulls;
  
         if (next_elem >= num_elems)
         {
             next_elem = 0;
             found = false;      /* need to advance next array key */
         }
         else
             found = true;
         scan_key->sk_argument = elem_values[next_elem];
         if (elem_nulls[next_elem])
             scan_key->sk_flags |= SK_ISNULL;
         else
             scan_key->sk_flags &= ~SK_ISNULL;
         arrayKeys[j].next_elem = next_elem + 1;
         if (found)
             break;
     }
  
     return found;
 }

References IndexArrayKeyInfo::elem_nulls, IndexArrayKeyInfo::elem_values, j, IndexArrayKeyInfo::next_elem, IndexArrayKeyInfo::num_elems, IndexArrayKeyInfo::scan_key, ScanKeyData::sk_argument, ScanKeyData::sk_flags, and SK_ISNULL.

Referenced by MultiExecBitmapIndexScan().

◆ ExecIndexBuildScanKeys()

void ExecIndexBuildScanKeys	(	PlanState *	planstate,
		Relation	index,
		List *	quals,
		bool	isorderby,
		ScanKey *	scanKeys,
		int *	numScanKeys,
		IndexRuntimeKeyInfo **	runtimeKeys,
		int *	numRuntimeKeys,
		IndexArrayKeyInfo **	arrayKeys,
		int *	numArrayKeys
	)

Definition at line 1135 of file nodeIndexscan.c.

 {
     ListCell   *qual_cell;
     ScanKey     scan_keys;
     IndexRuntimeKeyInfo *runtime_keys;
     IndexArrayKeyInfo *array_keys;
     int         n_scan_keys;
     int         n_runtime_keys;
     int         max_runtime_keys;
     int         n_array_keys;
     int         j;
  
     /* Allocate array for ScanKey structs: one per qual */
     n_scan_keys = list_length(quals);
     scan_keys = (ScanKey) palloc(n_scan_keys * sizeof(ScanKeyData));
  
     /*
      * runtime_keys array is dynamically resized as needed.  We handle it this
      * way so that the same runtime keys array can be shared between
      * indexquals and indexorderbys, which will be processed in separate calls
      * of this function.  Caller must be sure to pass in NULL/0 for first
      * call.
      */
     runtime_keys = *runtimeKeys;
     n_runtime_keys = max_runtime_keys = *numRuntimeKeys;
  
     /* Allocate array_keys as large as it could possibly need to be */
     array_keys = (IndexArrayKeyInfo *)
         palloc0(n_scan_keys * sizeof(IndexArrayKeyInfo));
     n_array_keys = 0;
  
     /*
      * for each opclause in the given qual, convert the opclause into a single
      * scan key
      */
     j = 0;
     foreach(qual_cell, quals)
     {
         Expr       *clause = (Expr *) lfirst(qual_cell);
         ScanKey     this_scan_key = &scan_keys[j++];
         Oid         opno;       /* operator's OID */
         RegProcedure opfuncid;  /* operator proc id used in scan */
         Oid         opfamily;   /* opfamily of index column */
         int         op_strategy;    /* operator's strategy number */
         Oid         op_lefttype;    /* operator's declared input types */
         Oid         op_righttype;
         Expr       *leftop;     /* expr on lhs of operator */
         Expr       *rightop;    /* expr on rhs ... */
         AttrNumber  varattno;   /* att number used in scan */
         int         indnkeyatts;
  
         indnkeyatts = IndexRelationGetNumberOfKeyAttributes(index);
         if (IsA(clause, OpExpr))
         {
             /* indexkey op const or indexkey op expression */
             int         flags = 0;
             Datum       scanvalue;
  
             opno = ((OpExpr *) clause)->opno;
             opfuncid = ((OpExpr *) clause)->opfuncid;
  
             /*
              * leftop should be the index key Var, possibly relabeled
              */
             leftop = (Expr *) get_leftop(clause);
  
             if (leftop && IsA(leftop, RelabelType))
                 leftop = ((RelabelType *) leftop)->arg;
  
             Assert(leftop != NULL);
  
             if (!(IsA(leftop, Var) &&
                   ((Var *) leftop)->varno == INDEX_VAR))
                 elog(ERROR, "indexqual doesn't have key on left side");
  
             varattno = ((Var *) leftop)->varattno;
             if (varattno < 1 || varattno > indnkeyatts)
                 elog(ERROR, "bogus index qualification");
  
             /*
              * We have to look up the operator's strategy number.  This
              * provides a cross-check that the operator does match the index.
              */
             opfamily = index->rd_opfamily[varattno - 1];
  
             get_op_opfamily_properties(opno, opfamily, isorderby,
                                        &op_strategy,
                                        &op_lefttype,
                                        &op_righttype);
  
             if (isorderby)
                 flags |= SK_ORDER_BY;
  
             /*
              * rightop is the constant or variable comparison value
              */
             rightop = (Expr *) get_rightop(clause);
  
             if (rightop && IsA(rightop, RelabelType))
                 rightop = ((RelabelType *) rightop)->arg;
  
             Assert(rightop != NULL);
  
             if (IsA(rightop, Const))
             {
                 /* OK, simple constant comparison value */
                 scanvalue = ((Const *) rightop)->constvalue;
                 if (((Const *) rightop)->constisnull)
                     flags |= SK_ISNULL;
             }
             else
             {
                 /* Need to treat this one as a runtime key */
                 if (n_runtime_keys >= max_runtime_keys)
                 {
                     if (max_runtime_keys == 0)
                     {
                         max_runtime_keys = 8;
                         runtime_keys = (IndexRuntimeKeyInfo *)
                             palloc(max_runtime_keys * sizeof(IndexRuntimeKeyInfo));
                     }
                     else
                     {
                         max_runtime_keys *= 2;
                         runtime_keys = (IndexRuntimeKeyInfo *)
                             repalloc(runtime_keys, max_runtime_keys * sizeof(IndexRuntimeKeyInfo));
                     }
                 }
                 runtime_keys[n_runtime_keys].scan_key = this_scan_key;
                 runtime_keys[n_runtime_keys].key_expr =
                     ExecInitExpr(rightop, planstate);
                 runtime_keys[n_runtime_keys].key_toastable =
                     TypeIsToastable(op_righttype);
                 n_runtime_keys++;
                 scanvalue = (Datum) 0;
             }
  
             /*
              * initialize the scan key's fields appropriately
              */
             ScanKeyEntryInitialize(this_scan_key,
                                    flags,
                                    varattno,    /* attribute number to scan */
                                    op_strategy, /* op's strategy */
                                    op_righttype,    /* strategy subtype */
                                    ((OpExpr *) clause)->inputcollid,    /* collation */
                                    opfuncid,    /* reg proc to use */
                                    scanvalue);  /* constant */
         }
         else if (IsA(clause, RowCompareExpr))
         {
             /* (indexkey, indexkey, ...) op (expression, expression, ...) */
             RowCompareExpr *rc = (RowCompareExpr *) clause;
             ScanKey     first_sub_key;
             int         n_sub_key;
             ListCell   *largs_cell;
             ListCell   *rargs_cell;
             ListCell   *opnos_cell;
             ListCell   *collids_cell;
  
             Assert(!isorderby);
  
             first_sub_key = (ScanKey)
                 palloc(list_length(rc->opnos) * sizeof(ScanKeyData));
             n_sub_key = 0;
  
             /* Scan RowCompare columns and generate subsidiary ScanKey items */
             forfour(largs_cell, rc->largs, rargs_cell, rc->rargs,
                     opnos_cell, rc->opnos, collids_cell, rc->inputcollids)
             {
                 ScanKey     this_sub_key = &first_sub_key[n_sub_key];
                 int         flags = SK_ROW_MEMBER;
                 Datum       scanvalue;
                 Oid         inputcollation;
  
                 leftop = (Expr *) lfirst(largs_cell);
                 rightop = (Expr *) lfirst(rargs_cell);
                 opno = lfirst_oid(opnos_cell);
                 inputcollation = lfirst_oid(collids_cell);
  
                 /*
                  * leftop should be the index key Var, possibly relabeled
                  */
                 if (leftop && IsA(leftop, RelabelType))
                     leftop = ((RelabelType *) leftop)->arg;
  
                 Assert(leftop != NULL);
  
                 if (!(IsA(leftop, Var) &&
                       ((Var *) leftop)->varno == INDEX_VAR))
                     elog(ERROR, "indexqual doesn't have key on left side");
  
                 varattno = ((Var *) leftop)->varattno;
  
                 /*
                  * We have to look up the operator's associated btree support
                  * function
                  */
                 if (index->rd_rel->relam != BTREE_AM_OID ||
                     varattno < 1 || varattno > indnkeyatts)
                     elog(ERROR, "bogus RowCompare index qualification");
                 opfamily = index->rd_opfamily[varattno - 1];
  
                 get_op_opfamily_properties(opno, opfamily, isorderby,
                                            &op_strategy,
                                            &op_lefttype,
                                            &op_righttype);
  
                 if (op_strategy != rc->rctype)
                     elog(ERROR, "RowCompare index qualification contains wrong operator");
  
                 opfuncid = get_opfamily_proc(opfamily,
                                              op_lefttype,
                                              op_righttype,
                                              BTORDER_PROC);
                 if (!RegProcedureIsValid(opfuncid))
                     elog(ERROR, "missing support function %d(%u,%u) in opfamily %u",
                          BTORDER_PROC, op_lefttype, op_righttype, opfamily);
  
                 /*
                  * rightop is the constant or variable comparison value
                  */
                 if (rightop && IsA(rightop, RelabelType))
                     rightop = ((RelabelType *) rightop)->arg;
  
                 Assert(rightop != NULL);
  
                 if (IsA(rightop, Const))
                 {
                     /* OK, simple constant comparison value */
                     scanvalue = ((Const *) rightop)->constvalue;
                     if (((Const *) rightop)->constisnull)
                         flags |= SK_ISNULL;
                 }
                 else
                 {
                     /* Need to treat this one as a runtime key */
                     if (n_runtime_keys >= max_runtime_keys)
                     {
                         if (max_runtime_keys == 0)
                         {
                             max_runtime_keys = 8;
                             runtime_keys = (IndexRuntimeKeyInfo *)
                                 palloc(max_runtime_keys * sizeof(IndexRuntimeKeyInfo));
                         }
                         else
                         {
                             max_runtime_keys *= 2;
                             runtime_keys = (IndexRuntimeKeyInfo *)
                                 repalloc(runtime_keys, max_runtime_keys * sizeof(IndexRuntimeKeyInfo));
                         }
                     }
                     runtime_keys[n_runtime_keys].scan_key = this_sub_key;
                     runtime_keys[n_runtime_keys].key_expr =
                         ExecInitExpr(rightop, planstate);
                     runtime_keys[n_runtime_keys].key_toastable =
                         TypeIsToastable(op_righttype);
                     n_runtime_keys++;
                     scanvalue = (Datum) 0;
                 }
  
                 /*
                  * initialize the subsidiary scan key's fields appropriately
                  */
                 ScanKeyEntryInitialize(this_sub_key,
                                        flags,
                                        varattno,    /* attribute number */
                                        op_strategy, /* op's strategy */
                                        op_righttype,    /* strategy subtype */
                                        inputcollation,  /* collation */
                                        opfuncid,    /* reg proc to use */
                                        scanvalue);  /* constant */
                 n_sub_key++;
             }
  
             /* Mark the last subsidiary scankey correctly */
             first_sub_key[n_sub_key - 1].sk_flags |= SK_ROW_END;
  
             /*
              * We don't use ScanKeyEntryInitialize for the header because it
              * isn't going to contain a valid sk_func pointer.
              */
             MemSet(this_scan_key, 0, sizeof(ScanKeyData));
             this_scan_key->sk_flags = SK_ROW_HEADER;
             this_scan_key->sk_attno = first_sub_key->sk_attno;
             this_scan_key->sk_strategy = rc->rctype;
             /* sk_subtype, sk_collation, sk_func not used in a header */
             this_scan_key->sk_argument = PointerGetDatum(first_sub_key);
         }
         else if (IsA(clause, ScalarArrayOpExpr))
         {
             /* indexkey op ANY (array-expression) */
             ScalarArrayOpExpr *saop = (ScalarArrayOpExpr *) clause;
             int         flags = 0;
             Datum       scanvalue;
  
             Assert(!isorderby);
  
             Assert(saop->useOr);
             opno = saop->opno;
             opfuncid = saop->opfuncid;
  
             /*
              * leftop should be the index key Var, possibly relabeled
              */
             leftop = (Expr *) linitial(saop->args);
  
             if (leftop && IsA(leftop, RelabelType))
                 leftop = ((RelabelType *) leftop)->arg;
  
             Assert(leftop != NULL);
  
             if (!(IsA(leftop, Var) &&
                   ((Var *) leftop)->varno == INDEX_VAR))
                 elog(ERROR, "indexqual doesn't have key on left side");
  
             varattno = ((Var *) leftop)->varattno;
             if (varattno < 1 || varattno > indnkeyatts)
                 elog(ERROR, "bogus index qualification");
  
             /*
              * We have to look up the operator's strategy number.  This
              * provides a cross-check that the operator does match the index.
              */
             opfamily = index->rd_opfamily[varattno - 1];
  
             get_op_opfamily_properties(opno, opfamily, isorderby,
                                        &op_strategy,
                                        &op_lefttype,
                                        &op_righttype);
  
             /*
              * rightop is the constant or variable array value
              */
             rightop = (Expr *) lsecond(saop->args);
  
             if (rightop && IsA(rightop, RelabelType))
                 rightop = ((RelabelType *) rightop)->arg;
  
             Assert(rightop != NULL);
  
             if (index->rd_indam->amsearcharray)
             {
                 /* Index AM will handle this like a simple operator */
                 flags |= SK_SEARCHARRAY;
                 if (IsA(rightop, Const))
                 {
                     /* OK, simple constant comparison value */
                     scanvalue = ((Const *) rightop)->constvalue;
                     if (((Const *) rightop)->constisnull)
                         flags |= SK_ISNULL;
                 }
                 else
                 {
                     /* Need to treat this one as a runtime key */
                     if (n_runtime_keys >= max_runtime_keys)
                     {
                         if (max_runtime_keys == 0)
                         {
                             max_runtime_keys = 8;
                             runtime_keys = (IndexRuntimeKeyInfo *)
                                 palloc(max_runtime_keys * sizeof(IndexRuntimeKeyInfo));
                         }
                         else
                         {
                             max_runtime_keys *= 2;
                             runtime_keys = (IndexRuntimeKeyInfo *)
                                 repalloc(runtime_keys, max_runtime_keys * sizeof(IndexRuntimeKeyInfo));
                         }
                     }
                     runtime_keys[n_runtime_keys].scan_key = this_scan_key;
                     runtime_keys[n_runtime_keys].key_expr =
                         ExecInitExpr(rightop, planstate);
  
                     /*
                      * Careful here: the runtime expression is not of
                      * op_righttype, but rather is an array of same; so
                      * TypeIsToastable() isn't helpful.  However, we can
                      * assume that all array types are toastable.
                      */
                     runtime_keys[n_runtime_keys].key_toastable = true;
                     n_runtime_keys++;
                     scanvalue = (Datum) 0;
                 }
             }
             else
             {
                 /* Executor has to expand the array value */
                 array_keys[n_array_keys].scan_key = this_scan_key;
                 array_keys[n_array_keys].array_expr =
                     ExecInitExpr(rightop, planstate);
                 /* the remaining fields were zeroed by palloc0 */
                 n_array_keys++;
                 scanvalue = (Datum) 0;
             }
  
             /*
              * initialize the scan key's fields appropriately
              */
             ScanKeyEntryInitialize(this_scan_key,
                                    flags,
                                    varattno,    /* attribute number to scan */
                                    op_strategy, /* op's strategy */
                                    op_righttype,    /* strategy subtype */
                                    saop->inputcollid,   /* collation */
                                    opfuncid,    /* reg proc to use */
                                    scanvalue);  /* constant */
         }
         else if (IsA(clause, NullTest))
         {
             /* indexkey IS NULL or indexkey IS NOT NULL */
             NullTest   *ntest = (NullTest *) clause;
             int         flags;
  
             Assert(!isorderby);
  
             /*
              * argument should be the index key Var, possibly relabeled
              */
             leftop = ntest->arg;
  
             if (leftop && IsA(leftop, RelabelType))
                 leftop = ((RelabelType *) leftop)->arg;
  
             Assert(leftop != NULL);
  
             if (!(IsA(leftop, Var) &&
                   ((Var *) leftop)->varno == INDEX_VAR))
                 elog(ERROR, "NullTest indexqual has wrong key");
  
             varattno = ((Var *) leftop)->varattno;
  
             /*
              * initialize the scan key's fields appropriately
              */
             switch (ntest->nulltesttype)
             {
                 case IS_NULL:
                     flags = SK_ISNULL | SK_SEARCHNULL;
                     break;
                 case IS_NOT_NULL:
                     flags = SK_ISNULL | SK_SEARCHNOTNULL;
                     break;
                 default:
                     elog(ERROR, "unrecognized nulltesttype: %d",
                          (int) ntest->nulltesttype);
                     flags = 0;  /* keep compiler quiet */
                     break;
             }
  
             ScanKeyEntryInitialize(this_scan_key,
                                    flags,
                                    varattno,    /* attribute number to scan */
                                    InvalidStrategy, /* no strategy */
                                    InvalidOid,  /* no strategy subtype */
                                    InvalidOid,  /* no collation */
                                    InvalidOid,  /* no reg proc for this */
                                    (Datum) 0);  /* constant */
         }
         else
             elog(ERROR, "unsupported indexqual type: %d",
                  (int) nodeTag(clause));
     }
  
     Assert(n_runtime_keys <= max_runtime_keys);
  
     /* Get rid of any unused arrays */
     if (n_array_keys == 0)
     {
         pfree(array_keys);
         array_keys = NULL;
     }
  
     /*
      * Return info to our caller.
      */
     *scanKeys = scan_keys;
     *numScanKeys = n_scan_keys;
     *runtimeKeys = runtime_keys;
     *numRuntimeKeys = n_runtime_keys;
     if (arrayKeys)
     {
         *arrayKeys = array_keys;
         *numArrayKeys = n_array_keys;
     }
     else if (n_array_keys != 0)
         elog(ERROR, "ScalarArrayOpExpr index qual found where not allowed");
 }

References arg, NullTest::arg, ScalarArrayOpExpr::args, IndexArrayKeyInfo::array_expr, Assert, BTORDER_PROC, elog, ERROR, ExecInitExpr(), forfour, get_leftop(), get_op_opfamily_properties(), get_opfamily_proc(), get_rightop(), INDEX_VAR, IndexRelationGetNumberOfKeyAttributes, InvalidOid, InvalidStrategy, IS_NOT_NULL, IS_NULL, IsA, j, IndexRuntimeKeyInfo::key_expr, IndexRuntimeKeyInfo::key_toastable, RowCompareExpr::largs, lfirst, lfirst_oid, linitial, list_length(), lsecond, MemSet, nodeTag, NullTest::nulltesttype, ScalarArrayOpExpr::opno, palloc(), palloc0(), pfree(), PointerGetDatum(), RowCompareExpr::rargs, RowCompareExpr::rctype, RegProcedureIsValid, repalloc(), IndexRuntimeKeyInfo::scan_key, IndexArrayKeyInfo::scan_key, ScanKeyEntryInitialize(), ScanKeyData::sk_argument, ScanKeyData::sk_attno, ScanKeyData::sk_flags, SK_ISNULL, SK_ORDER_BY, SK_ROW_END, SK_ROW_HEADER, SK_ROW_MEMBER, SK_SEARCHARRAY, SK_SEARCHNOTNULL, SK_SEARCHNULL, ScanKeyData::sk_strategy, TypeIsToastable, and ScalarArrayOpExpr::useOr.

Referenced by ExecInitBitmapIndexScan(), ExecInitIndexOnlyScan(), and ExecInitIndexScan().

◆ ExecIndexEvalArrayKeys()

bool ExecIndexEvalArrayKeys	(	ExprContext *	econtext,
		IndexArrayKeyInfo *	arrayKeys,
		int	numArrayKeys
	)

Definition at line 661 of file nodeIndexscan.c.

 {
     bool        result = true;
     int         j;
     MemoryContext oldContext;
  
     /* We want to keep the arrays in per-tuple memory */
     oldContext = MemoryContextSwitchTo(econtext->ecxt_per_tuple_memory);
  
     for (j = 0; j < numArrayKeys; j++)
     {
         ScanKey     scan_key = arrayKeys[j].scan_key;
         ExprState  *array_expr = arrayKeys[j].array_expr;
         Datum       arraydatum;
         bool        isNull;
         ArrayType  *arrayval;
         int16       elmlen;
         bool        elmbyval;
         char        elmalign;
         int         num_elems;
         Datum      *elem_values;
         bool       *elem_nulls;
  
         /*
          * Compute and deconstruct the array expression. (Notes in
          * ExecIndexEvalRuntimeKeys() apply here too.)
          */
         arraydatum = ExecEvalExpr(array_expr,
                                   econtext,
                                   &isNull);
         if (isNull)
         {
             result = false;
             break;              /* no point in evaluating more */
         }
         arrayval = DatumGetArrayTypeP(arraydatum);
         /* We could cache this data, but not clear it's worth it */
         get_typlenbyvalalign(ARR_ELEMTYPE(arrayval),
                              &elmlen, &elmbyval, &elmalign);
         deconstruct_array(arrayval,
                           ARR_ELEMTYPE(arrayval),
                           elmlen, elmbyval, elmalign,
                           &elem_values, &elem_nulls, &num_elems);
         if (num_elems <= 0)
         {
             result = false;
             break;              /* no point in evaluating more */
         }
  
         /*
          * Note: we expect the previous array data, if any, to be
          * automatically freed by resetting the per-tuple context; hence no
          * pfree's here.
          */
         arrayKeys[j].elem_values = elem_values;
         arrayKeys[j].elem_nulls = elem_nulls;
         arrayKeys[j].num_elems = num_elems;
         scan_key->sk_argument = elem_values[0];
         if (elem_nulls[0])
             scan_key->sk_flags |= SK_ISNULL;
         else
             scan_key->sk_flags &= ~SK_ISNULL;
         arrayKeys[j].next_elem = 1;
     }
  
     MemoryContextSwitchTo(oldContext);
  
     return result;
 }

References ARR_ELEMTYPE, IndexArrayKeyInfo::array_expr, DatumGetArrayTypeP, deconstruct_array(), ExprContext::ecxt_per_tuple_memory, IndexArrayKeyInfo::elem_nulls, IndexArrayKeyInfo::elem_values, ExecEvalExpr(), get_typlenbyvalalign(), j, MemoryContextSwitchTo(), IndexArrayKeyInfo::next_elem, IndexArrayKeyInfo::num_elems, IndexArrayKeyInfo::scan_key, ScanKeyData::sk_argument, ScanKeyData::sk_flags, and SK_ISNULL.

Referenced by ExecReScanBitmapIndexScan().

◆ ExecIndexEvalRuntimeKeys()

void ExecIndexEvalRuntimeKeys	(	ExprContext *	econtext,
		IndexRuntimeKeyInfo *	runtimeKeys,
		int	numRuntimeKeys
	)

Definition at line 599 of file nodeIndexscan.c.

 {
     int         j;
     MemoryContext oldContext;
  
     /* We want to keep the key values in per-tuple memory */
     oldContext = MemoryContextSwitchTo(econtext->ecxt_per_tuple_memory);
  
     for (j = 0; j < numRuntimeKeys; j++)
     {
         ScanKey     scan_key = runtimeKeys[j].scan_key;
         ExprState  *key_expr = runtimeKeys[j].key_expr;
         Datum       scanvalue;
         bool        isNull;
  
         /*
          * For each run-time key, extract the run-time expression and evaluate
          * it with respect to the current context.  We then stick the result
          * into the proper scan key.
          *
          * Note: the result of the eval could be a pass-by-ref value that's
          * stored in some outer scan's tuple, not in
          * econtext->ecxt_per_tuple_memory.  We assume that the outer tuple
          * will stay put throughout our scan.  If this is wrong, we could copy
          * the result into our context explicitly, but I think that's not
          * necessary.
          *
          * It's also entirely possible that the result of the eval is a
          * toasted value.  In this case we should forcibly detoast it, to
          * avoid repeat detoastings each time the value is examined by an
          * index support function.
          */
         scanvalue = ExecEvalExpr(key_expr,
                                  econtext,
                                  &isNull);
         if (isNull)
         {
             scan_key->sk_argument = scanvalue;
             scan_key->sk_flags |= SK_ISNULL;
         }
         else
         {
             if (runtimeKeys[j].key_toastable)
                 scanvalue = PointerGetDatum(PG_DETOAST_DATUM(scanvalue));
             scan_key->sk_argument = scanvalue;
             scan_key->sk_flags &= ~SK_ISNULL;
         }
     }
  
     MemoryContextSwitchTo(oldContext);
 }

References ExprContext::ecxt_per_tuple_memory, ExecEvalExpr(), j, IndexRuntimeKeyInfo::key_expr, MemoryContextSwitchTo(), PG_DETOAST_DATUM, PointerGetDatum(), IndexRuntimeKeyInfo::scan_key, ScanKeyData::sk_argument, ScanKeyData::sk_flags, and SK_ISNULL.

Referenced by ExecReScanBitmapIndexScan(), ExecReScanIndexOnlyScan(), and ExecReScanIndexScan().

◆ ExecIndexMarkPos()

void ExecIndexMarkPos ( IndexScanState * node )

Definition at line 813 of file nodeIndexscan.c.

 {
     EState     *estate = node->ss.ps.state;
     EPQState   *epqstate = estate->es_epq_active;
  
     if (epqstate != NULL)
     {
         /*
          * We are inside an EvalPlanQual recheck.  If a test tuple exists for
          * this relation, then we shouldn't access the index at all.  We would
          * instead need to save, and later restore, the state of the
          * relsubs_done flag, so that re-fetching the test tuple is possible.
          * However, given the assumption that no caller sets a mark at the
          * start of the scan, we can only get here with relsubs_done[i]
          * already set, and so no state need be saved.
          */
         Index       scanrelid = ((Scan *) node->ss.ps.plan)->scanrelid;
  
         Assert(scanrelid > 0);
         if (epqstate->relsubs_slot[scanrelid - 1] != NULL ||
             epqstate->relsubs_rowmark[scanrelid - 1] != NULL)
         {
             /* Verify the claim above */
             if (!epqstate->relsubs_done[scanrelid - 1])
                 elog(ERROR, "unexpected ExecIndexMarkPos call in EPQ recheck");
             return;
         }
     }
  
     index_markpos(node->iss_ScanDesc);
 }

References Assert, elog, ERROR, EState::es_epq_active, index_markpos(), IndexScanState::iss_ScanDesc, PlanState::plan, ScanState::ps, EPQState::relsubs_done, EPQState::relsubs_rowmark, EPQState::relsubs_slot, IndexScanState::ss, and PlanState::state.

Referenced by ExecMarkPos().

◆ ExecIndexRestrPos()

void ExecIndexRestrPos ( IndexScanState * node )

Definition at line 850 of file nodeIndexscan.c.

 {
     EState     *estate = node->ss.ps.state;
     EPQState   *epqstate = estate->es_epq_active;
  
     if (estate->es_epq_active != NULL)
     {
         /* See comments in ExecIndexMarkPos */
         Index       scanrelid = ((Scan *) node->ss.ps.plan)->scanrelid;
  
         Assert(scanrelid > 0);
         if (epqstate->relsubs_slot[scanrelid - 1] != NULL ||
             epqstate->relsubs_rowmark[scanrelid - 1] != NULL)
         {
             /* Verify the claim above */
             if (!epqstate->relsubs_done[scanrelid - 1])
                 elog(ERROR, "unexpected ExecIndexRestrPos call in EPQ recheck");
             return;
         }
     }
  
     index_restrpos(node->iss_ScanDesc);
 }

References Assert, elog, ERROR, EState::es_epq_active, index_restrpos(), IndexScanState::iss_ScanDesc, PlanState::plan, ScanState::ps, EPQState::relsubs_done, EPQState::relsubs_rowmark, EPQState::relsubs_slot, IndexScanState::ss, and PlanState::state.

Referenced by ExecRestrPos().

◆ ExecIndexScan()

static TupleTableSlot* ExecIndexScan ( PlanState * pstate )

static

Definition at line 519 of file nodeIndexscan.c.

 {
     IndexScanState *node = castNode(IndexScanState, pstate);
  
     /*
      * If we have runtime keys and they've not already been set up, do it now.
      */
     if (node->iss_NumRuntimeKeys != 0 && !node->iss_RuntimeKeysReady)
         ExecReScan((PlanState *) node);
  
     if (node->iss_NumOrderByKeys > 0)
         return ExecScan(&node->ss,
                         (ExecScanAccessMtd) IndexNextWithReorder,
                         (ExecScanRecheckMtd) IndexRecheck);
     else
         return ExecScan(&node->ss,
                         (ExecScanAccessMtd) IndexNext,
                         (ExecScanRecheckMtd) IndexRecheck);
 }

References castNode, ExecReScan(), ExecScan(), IndexNext(), IndexNextWithReorder(), IndexRecheck(), IndexScanState::iss_NumOrderByKeys, IndexScanState::iss_NumRuntimeKeys, IndexScanState::iss_RuntimeKeysReady, and IndexScanState::ss.

Referenced by ExecInitIndexScan().

◆ ExecIndexScanEstimate()

void ExecIndexScanEstimate	(	IndexScanState *	node,
		ParallelContext *	pcxt
	)

Definition at line 1641 of file nodeIndexscan.c.

 {
     EState     *estate = node->ss.ps.state;
  
     node->iss_PscanLen = index_parallelscan_estimate(node->iss_RelationDesc,
                                                      node->iss_NumScanKeys,
                                                      node->iss_NumOrderByKeys,
                                                      estate->es_snapshot);
     shm_toc_estimate_chunk(&pcxt->estimator, node->iss_PscanLen);
     shm_toc_estimate_keys(&pcxt->estimator, 1);
 }

References EState::es_snapshot, ParallelContext::estimator, index_parallelscan_estimate(), IndexScanState::iss_NumOrderByKeys, IndexScanState::iss_NumScanKeys, IndexScanState::iss_PscanLen, IndexScanState::iss_RelationDesc, ScanState::ps, shm_toc_estimate_chunk, shm_toc_estimate_keys, IndexScanState::ss, and PlanState::state.

Referenced by ExecParallelEstimate().

◆ ExecIndexScanInitializeDSM()

void ExecIndexScanInitializeDSM	(	IndexScanState *	node,
		ParallelContext *	pcxt
	)

Definition at line 1661 of file nodeIndexscan.c.

 {
     EState     *estate = node->ss.ps.state;
     ParallelIndexScanDesc piscan;
  
     piscan = shm_toc_allocate(pcxt->toc, node->iss_PscanLen);
     index_parallelscan_initialize(node->ss.ss_currentRelation,
                                   node->iss_RelationDesc,
                                   estate->es_snapshot,
                                   piscan);
     shm_toc_insert(pcxt->toc, node->ss.ps.plan->plan_node_id, piscan);
     node->iss_ScanDesc =
         index_beginscan_parallel(node->ss.ss_currentRelation,
                                  node->iss_RelationDesc,
                                  node->iss_NumScanKeys,
                                  node->iss_NumOrderByKeys,
                                  piscan);
  
     /*
      * If no run-time keys to calculate or they are ready, go ahead and pass
      * the scankeys to the index AM.
      */
     if (node->iss_NumRuntimeKeys == 0 || node->iss_RuntimeKeysReady)
         index_rescan(node->iss_ScanDesc,
                      node->iss_ScanKeys, node->iss_NumScanKeys,
                      node->iss_OrderByKeys, node->iss_NumOrderByKeys);
 }

Referenced by ExecParallelInitializeDSM().

◆ ExecIndexScanInitializeWorker()

void ExecIndexScanInitializeWorker	(	IndexScanState *	node,
		ParallelWorkerContext *	pwcxt
	)

Definition at line 1710 of file nodeIndexscan.c.

 {
     ParallelIndexScanDesc piscan;
  
     piscan = shm_toc_lookup(pwcxt->toc, node->ss.ps.plan->plan_node_id, false);
     node->iss_ScanDesc =
         index_beginscan_parallel(node->ss.ss_currentRelation,
                                  node->iss_RelationDesc,
                                  node->iss_NumScanKeys,
                                  node->iss_NumOrderByKeys,
                                  piscan);
  
     /*
      * If no run-time keys to calculate or they are ready, go ahead and pass
      * the scankeys to the index AM.
      */
     if (node->iss_NumRuntimeKeys == 0 || node->iss_RuntimeKeysReady)
         index_rescan(node->iss_ScanDesc,
                      node->iss_ScanKeys, node->iss_NumScanKeys,
                      node->iss_OrderByKeys, node->iss_NumOrderByKeys);
 }

References index_beginscan_parallel(), index_rescan(), IndexScanState::iss_NumOrderByKeys, IndexScanState::iss_NumRuntimeKeys, IndexScanState::iss_NumScanKeys, IndexScanState::iss_OrderByKeys, IndexScanState::iss_RelationDesc, IndexScanState::iss_RuntimeKeysReady, IndexScanState::iss_ScanDesc, IndexScanState::iss_ScanKeys, PlanState::plan, Plan::plan_node_id, ScanState::ps, shm_toc_lookup(), IndexScanState::ss, ScanState::ss_currentRelation, and ParallelWorkerContext::toc.

Referenced by ExecParallelInitializeWorker().

◆ ExecIndexScanReInitializeDSM()

void ExecIndexScanReInitializeDSM	(	IndexScanState *	node,
		ParallelContext *	pcxt
	)

Definition at line 1697 of file nodeIndexscan.c.

 {
     index_parallelrescan(node->iss_ScanDesc);
 }

References index_parallelrescan(), and IndexScanState::iss_ScanDesc.

Referenced by ExecParallelReInitializeDSM().

◆ ExecInitIndexScan()

IndexScanState* ExecInitIndexScan	(	IndexScan *	node,
		EState *	estate,
		int	eflags
	)

Definition at line 886 of file nodeIndexscan.c.

 {
     IndexScanState *indexstate;
     Relation    currentRelation;
     LOCKMODE    lockmode;
  
     /*
      * create state structure
      */
     indexstate = makeNode(IndexScanState);
     indexstate->ss.ps.plan = (Plan *) node;
     indexstate->ss.ps.state = estate;
     indexstate->ss.ps.ExecProcNode = ExecIndexScan;
  
     /*
      * Miscellaneous initialization
      *
      * create expression context for node
      */
     ExecAssignExprContext(estate, &indexstate->ss.ps);
  
     /*
      * open the scan relation
      */
     currentRelation = ExecOpenScanRelation(estate, node->scan.scanrelid, eflags);
  
     indexstate->ss.ss_currentRelation = currentRelation;
     indexstate->ss.ss_currentScanDesc = NULL;   /* no heap scan here */
  
     /*
      * get the scan type from the relation descriptor.
      */
     ExecInitScanTupleSlot(estate, &indexstate->ss,
                           RelationGetDescr(currentRelation),
                           table_slot_callbacks(currentRelation));
  
     /*
      * Initialize result type and projection.
      */
     ExecInitResultTypeTL(&indexstate->ss.ps);
     ExecAssignScanProjectionInfo(&indexstate->ss);
  
     /*
      * initialize child expressions
      *
      * Note: we don't initialize all of the indexqual expression, only the
      * sub-parts corresponding to runtime keys (see below).  Likewise for
      * indexorderby, if any.  But the indexqualorig expression is always
      * initialized even though it will only be used in some uncommon cases ---
      * would be nice to improve that.  (Problem is that any SubPlans present
      * in the expression must be found now...)
      */
     indexstate->ss.ps.qual =
         ExecInitQual(node->scan.plan.qual, (PlanState *) indexstate);
     indexstate->indexqualorig =
         ExecInitQual(node->indexqualorig, (PlanState *) indexstate);
     indexstate->indexorderbyorig =
         ExecInitExprList(node->indexorderbyorig, (PlanState *) indexstate);
  
     /*
      * If we are just doing EXPLAIN (ie, aren't going to run the plan), stop
      * here.  This allows an index-advisor plugin to EXPLAIN a plan containing
      * references to nonexistent indexes.
      */
     if (eflags & EXEC_FLAG_EXPLAIN_ONLY)
         return indexstate;
  
     /* Open the index relation. */
     lockmode = exec_rt_fetch(node->scan.scanrelid, estate)->rellockmode;
     indexstate->iss_RelationDesc = index_open(node->indexid, lockmode);
  
     /*
      * Initialize index-specific scan state
      */
     indexstate->iss_RuntimeKeysReady = false;
     indexstate->iss_RuntimeKeys = NULL;
     indexstate->iss_NumRuntimeKeys = 0;
  
     /*
      * build the index scan keys from the index qualification
      */
     ExecIndexBuildScanKeys((PlanState *) indexstate,
                            indexstate->iss_RelationDesc,
                            node->indexqual,
                            false,
                            &indexstate->iss_ScanKeys,
                            &indexstate->iss_NumScanKeys,
                            &indexstate->iss_RuntimeKeys,
                            &indexstate->iss_NumRuntimeKeys,
                            NULL,    /* no ArrayKeys */
                            NULL);
  
     /*
      * any ORDER BY exprs have to be turned into scankeys in the same way
      */
     ExecIndexBuildScanKeys((PlanState *) indexstate,
                            indexstate->iss_RelationDesc,
                            node->indexorderby,
                            true,
                            &indexstate->iss_OrderByKeys,
                            &indexstate->iss_NumOrderByKeys,
                            &indexstate->iss_RuntimeKeys,
                            &indexstate->iss_NumRuntimeKeys,
                            NULL,    /* no ArrayKeys */
                            NULL);
  
     /* Initialize sort support, if we need to re-check ORDER BY exprs */
     if (indexstate->iss_NumOrderByKeys > 0)
     {
         int         numOrderByKeys = indexstate->iss_NumOrderByKeys;
         int         i;
         ListCell   *lco;
         ListCell   *lcx;
  
         /*
          * Prepare sort support, and look up the data type for each ORDER BY
          * expression.
          */
         Assert(numOrderByKeys == list_length(node->indexorderbyops));
         Assert(numOrderByKeys == list_length(node->indexorderbyorig));
         indexstate->iss_SortSupport = (SortSupportData *)
             palloc0(numOrderByKeys * sizeof(SortSupportData));
         indexstate->iss_OrderByTypByVals = (bool *)
             palloc(numOrderByKeys * sizeof(bool));
         indexstate->iss_OrderByTypLens = (int16 *)
             palloc(numOrderByKeys * sizeof(int16));
         i = 0;
         forboth(lco, node->indexorderbyops, lcx, node->indexorderbyorig)
         {
             Oid         orderbyop = lfirst_oid(lco);
             Node       *orderbyexpr = (Node *) lfirst(lcx);
             Oid         orderbyType = exprType(orderbyexpr);
             Oid         orderbyColl = exprCollation(orderbyexpr);
             SortSupport orderbysort = &indexstate->iss_SortSupport[i];
  
             /* Initialize sort support */
             orderbysort->ssup_cxt = CurrentMemoryContext;
             orderbysort->ssup_collation = orderbyColl;
             /* See cmp_orderbyvals() comments on NULLS LAST */
             orderbysort->ssup_nulls_first = false;
             /* ssup_attno is unused here and elsewhere */
             orderbysort->ssup_attno = 0;
             /* No abbreviation */
             orderbysort->abbreviate = false;
             PrepareSortSupportFromOrderingOp(orderbyop, orderbysort);
  
             get_typlenbyval(orderbyType,
                             &indexstate->iss_OrderByTypLens[i],
                             &indexstate->iss_OrderByTypByVals[i]);
             i++;
         }
  
         /* allocate arrays to hold the re-calculated distances */
         indexstate->iss_OrderByValues = (Datum *)
             palloc(numOrderByKeys * sizeof(Datum));
         indexstate->iss_OrderByNulls = (bool *)
             palloc(numOrderByKeys * sizeof(bool));
  
         /* and initialize the reorder queue */
         indexstate->iss_ReorderQueue = pairingheap_allocate(reorderqueue_cmp,
                                                             indexstate);
     }
  
     /*
      * If we have runtime keys, we need an ExprContext to evaluate them. The
      * node's standard context won't do because we want to reset that context
      * for every tuple.  So, build another context just like the other one...
      * -tgl 7/11/00
      */
     if (indexstate->iss_NumRuntimeKeys != 0)
     {
         ExprContext *stdecontext = indexstate->ss.ps.ps_ExprContext;
  
         ExecAssignExprContext(estate, &indexstate->ss.ps);
         indexstate->iss_RuntimeContext = indexstate->ss.ps.ps_ExprContext;
         indexstate->ss.ps.ps_ExprContext = stdecontext;
     }
     else
     {
         indexstate->iss_RuntimeContext = NULL;
     }
  
     /*
      * all done.
      */
     return indexstate;
 }

Referenced by ExecInitNode().

◆ ExecReScanIndexScan()

void ExecReScanIndexScan ( IndexScanState * node )

Definition at line 551 of file nodeIndexscan.c.

 {
     /*
      * If we are doing runtime key calculations (ie, any of the index key
      * values weren't simple Consts), compute the new key values.  But first,
      * reset the context so we don't leak memory as each outer tuple is
      * scanned.  Note this assumes that we will recalculate *all* runtime keys
      * on each call.
      */
     if (node->iss_NumRuntimeKeys != 0)
     {
         ExprContext *econtext = node->iss_RuntimeContext;
  
         ResetExprContext(econtext);
         ExecIndexEvalRuntimeKeys(econtext,
                                  node->iss_RuntimeKeys,
                                  node->iss_NumRuntimeKeys);
     }
     node->iss_RuntimeKeysReady = true;
  
     /* flush the reorder queue */
     if (node->iss_ReorderQueue)
     {
         HeapTuple   tuple;
  
         while (!pairingheap_is_empty(node->iss_ReorderQueue))
         {
             tuple = reorderqueue_pop(node);
             heap_freetuple(tuple);
         }
     }
  
     /* reset index scan */
     if (node->iss_ScanDesc)
         index_rescan(node->iss_ScanDesc,
                      node->iss_ScanKeys, node->iss_NumScanKeys,
                      node->iss_OrderByKeys, node->iss_NumOrderByKeys);
     node->iss_ReachedEnd = false;
  
     ExecScanReScan(&node->ss);
 }

Referenced by ExecReScan().

◆ IndexNext()

static TupleTableSlot * IndexNext ( IndexScanState * node )

static

Definition at line 80 of file nodeIndexscan.c.

 {
     EState     *estate;
     ExprContext *econtext;
     ScanDirection direction;
     IndexScanDesc scandesc;
     TupleTableSlot *slot;
  
     /*
      * extract necessary information from index scan node
      */
     estate = node->ss.ps.state;
  
     /*
      * Determine which direction to scan the index in based on the plan's scan
      * direction and the current direction of execution.
      */
     direction = ScanDirectionCombine(estate->es_direction,
                                      ((IndexScan *) node->ss.ps.plan)->indexorderdir);
     scandesc = node->iss_ScanDesc;
     econtext = node->ss.ps.ps_ExprContext;
     slot = node->ss.ss_ScanTupleSlot;
  
     if (scandesc == NULL)
     {
         /*
          * We reach here if the index scan is not parallel, or if we're
          * serially executing an index scan that was planned to be parallel.
          */
         scandesc = index_beginscan(node->ss.ss_currentRelation,
                                    node->iss_RelationDesc,
                                    estate->es_snapshot,
                                    node->iss_NumScanKeys,
                                    node->iss_NumOrderByKeys);
  
         node->iss_ScanDesc = scandesc;
  
         /*
          * If no run-time keys to calculate or they are ready, go ahead and
          * pass the scankeys to the index AM.
          */
         if (node->iss_NumRuntimeKeys == 0 || node->iss_RuntimeKeysReady)
             index_rescan(scandesc,
                          node->iss_ScanKeys, node->iss_NumScanKeys,
                          node->iss_OrderByKeys, node->iss_NumOrderByKeys);
     }
  
     /*
      * ok, now that we have what we need, fetch the next tuple.
      */
     while (index_getnext_slot(scandesc, direction, slot))
     {
         CHECK_FOR_INTERRUPTS();
  
         /*
          * If the index was lossy, we have to recheck the index quals using
          * the fetched tuple.
          */
         if (scandesc->xs_recheck)
         {
             econtext->ecxt_scantuple = slot;
             if (!ExecQualAndReset(node->indexqualorig, econtext))
             {
                 /* Fails recheck, so drop it and loop back for another */
                 InstrCountFiltered2(node, 1);
                 continue;
             }
         }
  
         return slot;
     }
  
     /*
      * if we get here it means the index scan failed so we are at the end of
      * the scan..
      */
     node->iss_ReachedEnd = true;
     return ExecClearTuple(slot);
 }

Referenced by ExecIndexScan().

◆ IndexNextWithReorder()

static TupleTableSlot * IndexNextWithReorder ( IndexScanState * node )

static

Definition at line 168 of file nodeIndexscan.c.

 {
     EState     *estate;
     ExprContext *econtext;
     IndexScanDesc scandesc;
     TupleTableSlot *slot;
     ReorderTuple *topmost = NULL;
     bool        was_exact;
     Datum      *lastfetched_vals;
     bool       *lastfetched_nulls;
     int         cmp;
  
     estate = node->ss.ps.state;
  
     /*
      * Only forward scan is supported with reordering.  Note: we can get away
      * with just Asserting here because the system will not try to run the
      * plan backwards if ExecSupportsBackwardScan() says it won't work.
      * Currently, that is guaranteed because no index AMs support both
      * amcanorderbyop and amcanbackward; if any ever do,
      * ExecSupportsBackwardScan() will need to consider indexorderbys
      * explicitly.
      */
     Assert(!ScanDirectionIsBackward(((IndexScan *) node->ss.ps.plan)->indexorderdir));
     Assert(ScanDirectionIsForward(estate->es_direction));
  
     scandesc = node->iss_ScanDesc;
     econtext = node->ss.ps.ps_ExprContext;
     slot = node->ss.ss_ScanTupleSlot;
  
     if (scandesc == NULL)
     {
         /*
          * We reach here if the index scan is not parallel, or if we're
          * serially executing an index scan that was planned to be parallel.
          */
         scandesc = index_beginscan(node->ss.ss_currentRelation,
                                    node->iss_RelationDesc,
                                    estate->es_snapshot,
                                    node->iss_NumScanKeys,
                                    node->iss_NumOrderByKeys);
  
         node->iss_ScanDesc = scandesc;
  
         /*
          * If no run-time keys to calculate or they are ready, go ahead and
          * pass the scankeys to the index AM.
          */
         if (node->iss_NumRuntimeKeys == 0 || node->iss_RuntimeKeysReady)
             index_rescan(scandesc,
                          node->iss_ScanKeys, node->iss_NumScanKeys,
                          node->iss_OrderByKeys, node->iss_NumOrderByKeys);
     }
  
     for (;;)
     {
         CHECK_FOR_INTERRUPTS();
  
         /*
          * Check the reorder queue first.  If the topmost tuple in the queue
          * has an ORDER BY value smaller than (or equal to) the value last
          * returned by the index, we can return it now.
          */
         if (!pairingheap_is_empty(node->iss_ReorderQueue))
         {
             topmost = (ReorderTuple *) pairingheap_first(node->iss_ReorderQueue);
  
             if (node->iss_ReachedEnd ||
                 cmp_orderbyvals(topmost->orderbyvals,
                                 topmost->orderbynulls,
                                 scandesc->xs_orderbyvals,
                                 scandesc->xs_orderbynulls,
                                 node) <= 0)
             {
                 HeapTuple   tuple;
  
                 tuple = reorderqueue_pop(node);
  
                 /* Pass 'true', as the tuple in the queue is a palloc'd copy */
                 ExecForceStoreHeapTuple(tuple, slot, true);
                 return slot;
             }
         }
         else if (node->iss_ReachedEnd)
         {
             /* Queue is empty, and no more tuples from index.  We're done. */
             return ExecClearTuple(slot);
         }
  
         /*
          * Fetch next tuple from the index.
          */
 next_indextuple:
         if (!index_getnext_slot(scandesc, ForwardScanDirection, slot))
         {
             /*
              * No more tuples from the index.  But we still need to drain any
              * remaining tuples from the queue before we're done.
              */
             node->iss_ReachedEnd = true;
             continue;
         }
  
         /*
          * If the index was lossy, we have to recheck the index quals and
          * ORDER BY expressions using the fetched tuple.
          */
         if (scandesc->xs_recheck)
         {
             econtext->ecxt_scantuple = slot;
             if (!ExecQualAndReset(node->indexqualorig, econtext))
             {
                 /* Fails recheck, so drop it and loop back for another */
                 InstrCountFiltered2(node, 1);
                 /* allow this loop to be cancellable */
                 CHECK_FOR_INTERRUPTS();
                 goto next_indextuple;
             }
         }
  
         if (scandesc->xs_recheckorderby)
         {
             econtext->ecxt_scantuple = slot;
             ResetExprContext(econtext);
             EvalOrderByExpressions(node, econtext);
  
             /*
              * Was the ORDER BY value returned by the index accurate?  The
              * recheck flag means that the index can return inaccurate values,
              * but then again, the value returned for any particular tuple
              * could also be exactly correct.  Compare the value returned by
              * the index with the recalculated value.  (If the value returned
              * by the index happened to be exact right, we can often avoid
              * pushing the tuple to the queue, just to pop it back out again.)
              */
             cmp = cmp_orderbyvals(node->iss_OrderByValues,
                                   node->iss_OrderByNulls,
                                   scandesc->xs_orderbyvals,
                                   scandesc->xs_orderbynulls,
                                   node);
             if (cmp < 0)
                 elog(ERROR, "index returned tuples in wrong order");
             else if (cmp == 0)
                 was_exact = true;
             else
                 was_exact = false;
             lastfetched_vals = node->iss_OrderByValues;
             lastfetched_nulls = node->iss_OrderByNulls;
         }
         else
         {
             was_exact = true;
             lastfetched_vals = scandesc->xs_orderbyvals;
             lastfetched_nulls = scandesc->xs_orderbynulls;
         }
  
         /*
          * Can we return this tuple immediately, or does it need to be pushed
          * to the reorder queue?  If the ORDER BY expression values returned
          * by the index were inaccurate, we can't return it yet, because the
          * next tuple from the index might need to come before this one. Also,
          * we can't return it yet if there are any smaller tuples in the queue
          * already.
          */
         if (!was_exact || (topmost && cmp_orderbyvals(lastfetched_vals,
                                                       lastfetched_nulls,
                                                       topmost->orderbyvals,
                                                       topmost->orderbynulls,
                                                       node) > 0))
         {
             /* Put this tuple to the queue */
             reorderqueue_push(node, slot, lastfetched_vals, lastfetched_nulls);
             continue;
         }
         else
         {
             /* Can return this tuple immediately. */
             return slot;
         }
     }
  
     /*
      * if we get here it means the index scan failed so we are at the end of
      * the scan..
      */
     return ExecClearTuple(slot);
 }

Referenced by ExecIndexScan().

◆ IndexRecheck()

static bool IndexRecheck	(	IndexScanState *	node,
		TupleTableSlot *	slot
	)

static

Definition at line 386 of file nodeIndexscan.c.

 {
     ExprContext *econtext;
  
     /*
      * extract necessary information from index scan node
      */
     econtext = node->ss.ps.ps_ExprContext;
  
     /* Does the tuple meet the indexqual condition? */
     econtext->ecxt_scantuple = slot;
     return ExecQualAndReset(node->indexqualorig, econtext);
 }

References ExprContext::ecxt_scantuple, ExecQualAndReset(), IndexScanState::indexqualorig, ScanState::ps, PlanState::ps_ExprContext, and IndexScanState::ss.

Referenced by ExecIndexScan().

◆ reorderqueue_cmp()

static int reorderqueue_cmp	(	const pairingheap_node *	a,
		const pairingheap_node *	b,
		void *	arg
	)

static

Definition at line 441 of file nodeIndexscan.c.

 {
     ReorderTuple *rta = (ReorderTuple *) a;
     ReorderTuple *rtb = (ReorderTuple *) b;
     IndexScanState *node = (IndexScanState *) arg;
  
     /* exchange argument order to invert the sort order */
     return cmp_orderbyvals(rtb->orderbyvals, rtb->orderbynulls,
                            rta->orderbyvals, rta->orderbynulls,
                            node);
 }

References a, arg, b, cmp_orderbyvals(), ReorderTuple::orderbynulls, and ReorderTuple::orderbyvals.

Referenced by ExecInitIndexScan().

◆ reorderqueue_pop()

static HeapTuple reorderqueue_pop ( IndexScanState * node )

static

Definition at line 492 of file nodeIndexscan.c.

 {
     HeapTuple   result;
     ReorderTuple *topmost;
     int         i;
  
     topmost = (ReorderTuple *) pairingheap_remove_first(node->iss_ReorderQueue);
  
     result = topmost->htup;
     for (i = 0; i < node->iss_NumOrderByKeys; i++)
     {
         if (!node->iss_OrderByTypByVals[i] && !topmost->orderbynulls[i])
             pfree(DatumGetPointer(topmost->orderbyvals[i]));
     }
     pfree(topmost->orderbyvals);
     pfree(topmost->orderbynulls);
     pfree(topmost);
  
     return result;
 }

References DatumGetPointer(), ReorderTuple::htup, i, IndexScanState::iss_NumOrderByKeys, IndexScanState::iss_OrderByTypByVals, IndexScanState::iss_ReorderQueue, ReorderTuple::orderbynulls, ReorderTuple::orderbyvals, pairingheap_remove_first(), and pfree().

Referenced by ExecReScanIndexScan(), and IndexNextWithReorder().

◆ reorderqueue_push()

static void reorderqueue_push	(	IndexScanState *	node,
		TupleTableSlot *	slot,
		Datum *	orderbyvals,
		bool *	orderbynulls
	)

static

Definition at line 458 of file nodeIndexscan.c.

 {
     IndexScanDesc scandesc = node->iss_ScanDesc;
     EState     *estate = node->ss.ps.state;
     MemoryContext oldContext = MemoryContextSwitchTo(estate->es_query_cxt);
     ReorderTuple *rt;
     int         i;
  
     rt = (ReorderTuple *) palloc(sizeof(ReorderTuple));
     rt->htup = ExecCopySlotHeapTuple(slot);
     rt->orderbyvals =
         (Datum *) palloc(sizeof(Datum) * scandesc->numberOfOrderBys);
     rt->orderbynulls =
         (bool *) palloc(sizeof(bool) * scandesc->numberOfOrderBys);
     for (i = 0; i < node->iss_NumOrderByKeys; i++)
     {
         if (!orderbynulls[i])
             rt->orderbyvals[i] = datumCopy(orderbyvals[i],
                                            node->iss_OrderByTypByVals[i],
                                            node->iss_OrderByTypLens[i]);
         else
             rt->orderbyvals[i] = (Datum) 0;
         rt->orderbynulls[i] = orderbynulls[i];
     }
     pairingheap_add(node->iss_ReorderQueue, &rt->ph_node);
  
     MemoryContextSwitchTo(oldContext);
 }

References datumCopy(), EState::es_query_cxt, ExecCopySlotHeapTuple(), ReorderTuple::htup, i, IndexScanState::iss_NumOrderByKeys, IndexScanState::iss_OrderByTypByVals, IndexScanState::iss_OrderByTypLens, IndexScanState::iss_ReorderQueue, IndexScanState::iss_ScanDesc, MemoryContextSwitchTo(), IndexScanDescData::numberOfOrderBys, ReorderTuple::orderbynulls, ReorderTuple::orderbyvals, pairingheap_add(), palloc(), ReorderTuple::ph_node, ScanState::ps, IndexScanState::ss, and PlanState::state.

Referenced by IndexNextWithReorder().

Data Structures

Functions

Function Documentation

◆ cmp_orderbyvals()

◆ EvalOrderByExpressions()

◆ ExecEndIndexScan()

◆ ExecIndexAdvanceArrayKeys()

◆ ExecIndexBuildScanKeys()

◆ ExecIndexEvalArrayKeys()

◆ ExecIndexEvalRuntimeKeys()

◆ ExecIndexMarkPos()

◆ ExecIndexRestrPos()

◆ ExecIndexScan()

◆ ExecIndexScanEstimate()

◆ ExecIndexScanInitializeDSM()

◆ ExecIndexScanInitializeWorker()

◆ ExecIndexScanReInitializeDSM()

◆ ExecInitIndexScan()

◆ ExecReScanIndexScan()

◆ IndexNext()

◆ IndexNextWithReorder()

◆ IndexRecheck()

◆ reorderqueue_cmp()

◆ reorderqueue_pop()

◆ reorderqueue_push()