/*------------------------------------------------------------------------- * * nodeIndexscan.c * Routines to support indexes and indexed scans of relations * * Copyright (c) 1994, Regents of the University of California * * * IDENTIFICATION * $Header: /cvsroot/pgsql/src/backend/executor/nodeIndexscan.c,v 1.44 2000/01/19 23:54:55 tgl Exp $ * *------------------------------------------------------------------------- */ /* * INTERFACE ROUTINES * ExecInsertIndexTuples inserts tuples into indices on result relation * * ExecIndexScan scans a relation using indices * ExecIndexNext using index to retrieve next tuple * ExecInitIndexScan creates and initializes state info. * ExecIndexReScan rescans the indexed relation. * ExecEndIndexScan releases all storage. * ExecIndexMarkPos marks scan position. * ExecIndexRestrPos restores scan position. * * NOTES * the code supporting ExecInsertIndexTuples should be * collected and merged with the genam stuff. * */ #include "postgres.h" #include "access/genam.h" #include "access/heapam.h" #include "executor/execdebug.h" #include "executor/executor.h" #include "executor/nodeIndexscan.h" #include "nodes/nodeFuncs.h" #include "optimizer/clauses.h" #include "parser/parsetree.h" /* ---------------- * Misc stuff to move to executor.h soon -cim 6/5/90 * ---------------- */ #define NO_OP 0 #define LEFT_OP 1 #define RIGHT_OP 2 static TupleTableSlot *IndexNext(IndexScan *node); /* ---------------------------------------------------------------- * IndexNext * * Retrieve a tuple from the IndexScan node's currentRelation * using the indices in the IndexScanState information. * * note: the old code mentions 'Primary indices'. to my knowledge * we only support a single secondary index. -cim 9/11/89 * * old comments: * retrieve a tuple from relation using the indices given. * The indices are used in the order they appear in 'indices'. * The indices may be primary or secondary indices: * * primary index -- scan the relation 'relID' using keys supplied. * * secondary index -- scan the index relation to get the 'tid' for * a tuple in the relation 'relID'. * If the current index(pointed by 'indexPtr') fails to return a * tuple, the next index in the indices is used. * * bug fix so that it should retrieve on a null scan key. * ---------------------------------------------------------------- */ static TupleTableSlot * IndexNext(IndexScan *node) { EState *estate; CommonScanState *scanstate; IndexScanState *indexstate; ScanDirection direction; Snapshot snapshot; IndexScanDescPtr scanDescs; IndexScanDesc scandesc; Relation heapRelation; RetrieveIndexResult result; HeapTuple tuple; TupleTableSlot *slot; Buffer buffer = InvalidBuffer; int numIndices; bool bBackward; int indexNumber; /* ---------------- * extract necessary information from index scan node * ---------------- */ estate = node->scan.plan.state; direction = estate->es_direction; if (ScanDirectionIsBackward(node->indxorderdir)) { if (ScanDirectionIsForward(direction)) direction = BackwardScanDirection; else if (ScanDirectionIsBackward(direction)) direction = ForwardScanDirection; } snapshot = estate->es_snapshot; scanstate = node->scan.scanstate; indexstate = node->indxstate; scanDescs = indexstate->iss_ScanDescs; heapRelation = scanstate->css_currentRelation; numIndices = indexstate->iss_NumIndices; slot = scanstate->css_ScanTupleSlot; /* * Check if we are evaluating PlanQual for tuple of this relation. * Additional checking is not good, but no other way for now. We could * introduce new nodes for this case and handle IndexScan --> NewNode * switching in Init/ReScan plan... */ if (estate->es_evTuple != NULL && estate->es_evTuple[node->scan.scanrelid - 1] != NULL) { int iptr; ExecClearTuple(slot); if (estate->es_evTupleNull[node->scan.scanrelid - 1]) return slot; /* return empty slot */ /* probably ought to use ExecStoreTuple here... */ slot->val = estate->es_evTuple[node->scan.scanrelid - 1]; slot->ttc_shouldFree = false; for (iptr = 0; iptr < numIndices; iptr++) { scanstate->cstate.cs_ExprContext->ecxt_scantuple = slot; if (ExecQual(nth(iptr, node->indxqualorig), scanstate->cstate.cs_ExprContext, false)) break; } if (iptr == numIndices) /* would not be returned by indices */ slot->val = NULL; /* Flag for the next call that no more tuples */ estate->es_evTupleNull[node->scan.scanrelid - 1] = true; return (slot); } tuple = &(indexstate->iss_htup); /* ---------------- * ok, now that we have what we need, fetch an index tuple. * if scanning this index succeeded then return the * appropriate heap tuple.. else return NULL. * ---------------- */ bBackward = ScanDirectionIsBackward(direction); if (bBackward) { indexNumber = numIndices - indexstate->iss_IndexPtr - 1; if (indexNumber < 0) { indexNumber = 0; indexstate->iss_IndexPtr = numIndices - 1; } } else { if ((indexNumber = indexstate->iss_IndexPtr) < 0) { indexNumber = 0; indexstate->iss_IndexPtr = 0; } } while (indexNumber < numIndices) { scandesc = scanDescs[indexstate->iss_IndexPtr]; while ((result = index_getnext(scandesc, direction)) != NULL) { tuple->t_self = result->heap_iptr; heap_fetch(heapRelation, snapshot, tuple, &buffer); pfree(result); if (tuple->t_data != NULL) { bool prev_matches = false; int prev_index; /* ---------------- * store the scanned tuple in the scan tuple slot of * the scan state. Eventually we will only do this and not * return a tuple. Note: we pass 'false' because tuples * returned by amgetnext are pointers onto disk pages and * must not be pfree()'d. * ---------------- */ ExecStoreTuple(tuple, /* tuple to store */ slot, /* slot to store in */ buffer, /* buffer associated with tuple */ false); /* don't pfree */ /* * At this point we have an extra pin on the buffer, * because ExecStoreTuple incremented the pin count. * Drop our local pin. */ ReleaseBuffer(buffer); /* * We must check to see if the current tuple would have * been matched by an earlier index, so we don't double * report it. We do this by passing the tuple through * ExecQual and look for failure with all previous * qualifications. */ for (prev_index = 0; prev_index < indexstate->iss_IndexPtr; prev_index++) { scanstate->cstate.cs_ExprContext->ecxt_scantuple = slot; if (ExecQual(nth(prev_index, node->indxqualorig), scanstate->cstate.cs_ExprContext, false)) { prev_matches = true; break; } } if (!prev_matches) return slot; else ExecClearTuple(slot); } } if (indexNumber < numIndices) { indexNumber++; if (bBackward) indexstate->iss_IndexPtr--; else indexstate->iss_IndexPtr++; } } /* ---------------- * if we get here it means the index scan failed so we * are at the end of the scan.. * ---------------- */ return ExecClearTuple(slot); } /* ---------------------------------------------------------------- * ExecIndexScan(node) * * old comments: * Scans the relation using primary or secondary indices and returns * the next qualifying tuple in the direction specified. * It calls ExecScan() and passes it the access methods which returns * the next tuple using the indices. * * Conditions: * -- the "cursor" maintained by the AMI is positioned at the tuple * returned previously. * * Initial States: * -- the relation indicated is opened for scanning so that the * "cursor" is positioned before the first qualifying tuple. * -- all index realtions are opened for scanning. * -- indexPtr points to the first index. * -- state variable ruleFlag = nil. * ---------------------------------------------------------------- */ TupleTableSlot * ExecIndexScan(IndexScan *node) { /* ---------------- * use IndexNext as access method * ---------------- */ return ExecScan(&node->scan, IndexNext); } /* ---------------------------------------------------------------- * ExecIndexReScan(node) * * Recalculates the value of the scan keys whose value depends on * information known at runtime and rescans the indexed relation. * Updating the scan key was formerly done separately in * ExecUpdateIndexScanKeys. Integrating it into ReScan * makes rescans of indices and * relations/general streams more uniform. * * ---------------------------------------------------------------- */ void ExecIndexReScan(IndexScan *node, ExprContext *exprCtxt, Plan *parent) { EState *estate; IndexScanState *indexstate; ScanDirection direction; IndexScanDescPtr scanDescs; ScanKey *scanKeys; IndexScanDesc scan; ScanKey skey; int numIndices; int i; Pointer *runtimeKeyInfo; int *numScanKeys; List *indxqual; List *qual; int n_keys; ScanKey scan_keys; int *run_keys; int j; Expr *clause; Node *scanexpr; Datum scanvalue; bool isNull; bool isDone; indexstate = node->indxstate; estate = node->scan.plan.state; direction = estate->es_direction; numIndices = indexstate->iss_NumIndices; scanDescs = indexstate->iss_ScanDescs; scanKeys = indexstate->iss_ScanKeys; runtimeKeyInfo = (Pointer *) indexstate->iss_RuntimeKeyInfo; indxqual = node->indxqual; numScanKeys = indexstate->iss_NumScanKeys; indexstate->iss_IndexPtr = -1; if (ScanDirectionIsBackward(node->indxorderdir)) indexstate->iss_IndexPtr = numIndices; /* If this is re-scanning of PlanQual ... */ if (estate->es_evTuple != NULL && estate->es_evTuple[node->scan.scanrelid - 1] != NULL) { estate->es_evTupleNull[node->scan.scanrelid - 1] = false; return; } /* it's possible in subselects */ if (exprCtxt == NULL) exprCtxt = node->scan.scanstate->cstate.cs_ExprContext; node->scan.scanstate->cstate.cs_ExprContext->ecxt_outertuple = exprCtxt->ecxt_outertuple; /* * get the index qualifications and recalculate the appropriate values */ for (i = 0; i < numIndices; i++) { qual = nth(i, indxqual); n_keys = numScanKeys[i]; scan_keys = (ScanKey) scanKeys[i]; if (runtimeKeyInfo) { run_keys = (int *) runtimeKeyInfo[i]; for (j = 0; j < n_keys; j++) { /* * If we have a run-time key, then extract the run-time * expression and evaluate it with respect to the current * outer tuple. We then stick the result into the scan * key. */ if (run_keys[j] != NO_OP) { clause = nth(j, qual); scanexpr = (run_keys[j] == RIGHT_OP) ? (Node *) get_rightop(clause) : (Node *) get_leftop(clause); /* * pass in isDone but ignore it. We don't iterate in * quals */ scanvalue = (Datum) ExecEvalExpr(scanexpr, exprCtxt, &isNull, &isDone); scan_keys[j].sk_argument = scanvalue; if (isNull) scan_keys[j].sk_flags |= SK_ISNULL; else scan_keys[j].sk_flags &= ~SK_ISNULL; } } } scan = scanDescs[i]; skey = scanKeys[i]; index_rescan(scan, direction, skey); } /* ---------------- * perhaps return something meaningful * ---------------- */ return; } /* ---------------------------------------------------------------- * ExecEndIndexScan * * old comments * Releases any storage allocated through C routines. * Returns nothing. * ---------------------------------------------------------------- */ void ExecEndIndexScan(IndexScan *node) { CommonScanState *scanstate; IndexScanState *indexstate; Pointer *runtimeKeyInfo; ScanKey *scanKeys; List *indxqual; int *numScanKeys; int numIndices; int i; scanstate = node->scan.scanstate; indexstate = node->indxstate; indxqual = node->indxqual; runtimeKeyInfo = (Pointer *) indexstate->iss_RuntimeKeyInfo; /* ---------------- * extract information from the node * ---------------- */ numIndices = indexstate->iss_NumIndices; scanKeys = indexstate->iss_ScanKeys; numScanKeys = indexstate->iss_NumScanKeys; /* ---------------- * Free the projection info and the scan attribute info * * Note: we don't ExecFreeResultType(scanstate) * because the rule manager depends on the tupType * returned by ExecMain(). So for now, this * is freed at end-transaction time. -cim 6/2/91 * ---------------- */ ExecFreeProjectionInfo(&scanstate->cstate); /* ---------------- * close the heap and index relations * ---------------- */ ExecCloseR((Plan *) node); /* ---------------- * free the scan keys used in scanning the indices * ---------------- */ for (i = 0; i < numIndices; i++) { if (scanKeys[i] != NULL) pfree(scanKeys[i]); } pfree(scanKeys); pfree(numScanKeys); if (runtimeKeyInfo) { for (i = 0; i < numIndices; i++) { List *qual; int n_keys; qual = nth(i, indxqual); n_keys = length(qual); if (n_keys > 0) pfree(runtimeKeyInfo[i]); } pfree(runtimeKeyInfo); } /* ---------------- * clear out tuple table slots * ---------------- */ ExecClearTuple(scanstate->cstate.cs_ResultTupleSlot); ExecClearTuple(scanstate->css_ScanTupleSlot); /* ExecClearTuple(scanstate->css_RawTupleSlot); */ } /* ---------------------------------------------------------------- * ExecIndexMarkPos * * old comments * Marks scan position by marking the current index. * Returns nothing. * ---------------------------------------------------------------- */ void ExecIndexMarkPos(IndexScan *node) { IndexScanState *indexstate; IndexScanDescPtr indexScanDescs; IndexScanDesc scanDesc; int indexPtr; indexstate = node->indxstate; indexPtr = indexstate->iss_MarkIndexPtr = indexstate->iss_IndexPtr; indexScanDescs = indexstate->iss_ScanDescs; scanDesc = indexScanDescs[indexPtr]; #ifdef NOT_USED IndexScanMarkPosition(scanDesc); #endif index_markpos(scanDesc); } /* ---------------------------------------------------------------- * ExecIndexRestrPos * * old comments * Restores scan position by restoring the current index. * Returns nothing. * * XXX Assumes previously marked scan position belongs to current index * ---------------------------------------------------------------- */ void ExecIndexRestrPos(IndexScan *node) { IndexScanState *indexstate; IndexScanDescPtr indexScanDescs; IndexScanDesc scanDesc; int indexPtr; indexstate = node->indxstate; indexPtr = indexstate->iss_IndexPtr = indexstate->iss_MarkIndexPtr; indexScanDescs = indexstate->iss_ScanDescs; scanDesc = indexScanDescs[indexPtr]; #ifdef NOT_USED IndexScanRestorePosition(scanDesc); #endif index_restrpos(scanDesc); } /* ---------------------------------------------------------------- * ExecInitIndexScan * * Initializes the index scan's state information, creates * scan keys, and opens the base and index relations. * * Note: index scans have 2 sets of state information because * we have to keep track of the base relation and the * index relations. * * old comments * Creates the run-time state information for the node and * sets the relation id to contain relevant decriptors. * * Parameters: * node: IndexNode node produced by the planner. * estate: the execution state initialized in InitPlan. * ---------------------------------------------------------------- */ bool ExecInitIndexScan(IndexScan *node, EState *estate, Plan *parent) { IndexScanState *indexstate; CommonScanState *scanstate; List *indxqual; List *indxid; int i; int numIndices; int indexPtr; ScanKey *scanKeys; int *numScanKeys; RelationPtr relationDescs; IndexScanDescPtr scanDescs; Pointer *runtimeKeyInfo; bool have_runtime_keys; List *rangeTable; RangeTblEntry *rtentry; Index relid; Oid reloid; Relation currentRelation; HeapScanDesc currentScanDesc; ScanDirection direction; int baseid; List *execParam = NULL; /* ---------------- * assign execution state to node * ---------------- */ node->scan.plan.state = estate; /* -------------------------------- * Part 1) initialize scan state * * create new CommonScanState for node * -------------------------------- */ scanstate = makeNode(CommonScanState); /* scanstate->ss_ProcOuterFlag = false; scanstate->ss_OldRelId = 0; */ node->scan.scanstate = scanstate; /* ---------------- * assign node's base_id .. we don't use AssignNodeBaseid() because * the increment is done later on after we assign the index scan's * scanstate. see below. * ---------------- */ baseid = estate->es_BaseId; /* scanstate->csstate.cstate.bnode.base_id = baseid; */ scanstate->cstate.cs_base_id = baseid; /* ---------------- * create expression context for node * ---------------- */ ExecAssignExprContext(estate, &scanstate->cstate); #define INDEXSCAN_NSLOTS 3 /* ---------------- * tuple table initialization * ---------------- */ ExecInitResultTupleSlot(estate, &scanstate->cstate); ExecInitScanTupleSlot(estate, scanstate); /* ExecInitRawTupleSlot(estate, scanstate); */ /* ---------------- * initialize projection info. result type comes from scan desc * below.. * ---------------- */ ExecAssignProjectionInfo((Plan *) node, &scanstate->cstate); /* -------------------------------- * Part 2) initialize index scan state * * create new IndexScanState for node * -------------------------------- */ indexstate = makeNode(IndexScanState); indexstate->iss_NumIndices = 0; indexstate->iss_IndexPtr = -1; indexstate->iss_ScanKeys = NULL; indexstate->iss_NumScanKeys = NULL; indexstate->iss_RuntimeKeyInfo = NULL; indexstate->iss_RelationDescs = NULL; indexstate->iss_ScanDescs = NULL; node->indxstate = indexstate; /* ---------------- * assign base id to index scan state also * ---------------- */ indexstate->cstate.cs_base_id = baseid; baseid++; estate->es_BaseId = baseid; /* ---------------- * get the index node information * ---------------- */ indxid = node->indxid; indxqual = node->indxqual; numIndices = length(indxid); indexPtr = -1; CXT1_printf("ExecInitIndexScan: context is %d\n", CurrentMemoryContext); /* ---------------- * scanKeys is used to keep track of the ScanKey's. This is needed * because a single scan may use several indices and each index has * its own ScanKey. * ---------------- */ numScanKeys = (int *) palloc(numIndices * sizeof(int)); scanKeys = (ScanKey *) palloc(numIndices * sizeof(ScanKey)); relationDescs = (RelationPtr) palloc(numIndices * sizeof(Relation)); scanDescs = (IndexScanDescPtr) palloc(numIndices * sizeof(IndexScanDesc)); /* ---------------- * initialize runtime key info. * ---------------- */ have_runtime_keys = false; runtimeKeyInfo = (Pointer *) palloc(numIndices * sizeof(Pointer)); /* ---------------- * build the index scan keys from the index qualification * ---------------- */ for (i = 0; i < numIndices; i++) { int j; List *qual; int n_keys; ScanKey scan_keys; int *run_keys; qual = nth(i, indxqual); n_keys = length(qual); scan_keys = (n_keys <= 0) ? NULL : (ScanKey) palloc(n_keys * sizeof(ScanKeyData)); run_keys = (n_keys <= 0) ? NULL : (int *) palloc(n_keys * sizeof(int)); CXT1_printf("ExecInitIndexScan: context is %d\n", CurrentMemoryContext); /* ---------------- * for each opclause in the given qual, * convert each qual's opclause into a single scan key * ---------------- */ for (j = 0; j < n_keys; j++) { Expr *clause; /* one part of index qual */ Oper *op; /* operator used in scan.. */ Node *leftop; /* expr on lhs of operator */ Node *rightop;/* expr on rhs ... */ bits16 flags = 0; int scanvar;/* which var identifies varattno */ AttrNumber varattno = 0; /* att number used in scan */ Oid opid; /* operator id used in scan */ Datum scanvalue = 0; /* value used in scan (if const) */ /* ---------------- * extract clause information from the qualification * ---------------- */ clause = nth(j, qual); op = (Oper *) clause->oper; if (!IsA(op, Oper)) elog(ERROR, "ExecInitIndexScan: op not an Oper!"); opid = op->opid; /* ---------------- * Here we figure out the contents of the index qual. * The usual case is (var op const) or (const op var) * which means we form a scan key for the attribute * listed in the var node and use the value of the const. * * If we don't have a const node, then it means that * one of the var nodes refers to the "scan" tuple and * is used to determine which attribute to scan, and the * other expression is used to calculate the value used in * scanning the index. * * This means our index scan's scan key is a function of * information obtained during the execution of the plan * in which case we need to recalculate the index scan key * at run time. * * Hence, we set have_runtime_keys to true and then set * the appropriate flag in run_keys to LEFT_OP or RIGHT_OP. * The corresponding scan keys are recomputed at run time. * * XXX Although this code *thinks* it can handle an indexqual * with the indexkey on either side, in fact it cannot. * Indexscans only work with quals that have the indexkey on * the left (the planner/optimizer makes sure it never passes * anything else). The reason: the scankey machinery has no * provision for distinguishing which side of the operator is * the indexed attribute and which is the compared-to constant. * It just assumes that the attribute is on the left :-( * * I am leaving this code able to support both ways, even though * half of it is dead code, on the off chance that someone will * fix the scankey machinery someday --- tgl 8/11/99. * ---------------- */ scanvar = NO_OP; /* ---------------- * determine information in leftop * ---------------- */ leftop = (Node *) get_leftop(clause); Assert(leftop != NULL); if (IsA(leftop, Var) && var_is_rel((Var *) leftop)) { /* ---------------- * if the leftop is a "rel-var", then it means * that it is a var node which tells us which * attribute to use for our scan key. * ---------------- */ varattno = ((Var *) leftop)->varattno; scanvar = LEFT_OP; } else if (is_funcclause(leftop) && var_is_rel(lfirst(((Expr *) leftop)->args))) { /* ---------------- * if the leftop is a func node then it means * it identifies the value to place in our scan key. * Since functional indices have only one attribute * the attno must always be set to 1. * ---------------- */ varattno = 1; scanvar = LEFT_OP; } else if (IsA(leftop, Const)) { /* ---------------- * if the leftop is a const node then it means * it identifies the value to place in our scan key. * ---------------- */ run_keys[j] = NO_OP; scanvalue = ((Const *) leftop)->constvalue; } else if (IsA(leftop, Param)) { bool isnull; /* ---------------- * if the leftop is a Param node then it means * it identifies the value to place in our scan key. * ---------------- */ /* Life was so easy before ... subselects */ if (((Param *) leftop)->paramkind == PARAM_EXEC) { have_runtime_keys = true; run_keys[j] = LEFT_OP; execParam = lappendi(execParam, ((Param *) leftop)->paramid); } else { scanvalue = ExecEvalParam((Param *) leftop, scanstate->cstate.cs_ExprContext, &isnull); if (isnull) flags |= SK_ISNULL; run_keys[j] = NO_OP; } } else { /* ---------------- * otherwise, the leftop contains information usable * at runtime to figure out the value to place in our * scan key. * ---------------- */ have_runtime_keys = true; run_keys[j] = LEFT_OP; scanvalue = Int32GetDatum((int32) true); } /* ---------------- * now determine information in rightop * ---------------- */ rightop = (Node *) get_rightop(clause); Assert(rightop != NULL); if (IsA(rightop, Var) && var_is_rel((Var *) rightop)) { /* ---------------- * here we make sure only one op identifies the * scan-attribute... * ---------------- */ if (scanvar == LEFT_OP) elog(ERROR, "ExecInitIndexScan: %s", "both left and right op's are rel-vars"); /* ---------------- * if the rightop is a "rel-var", then it means * that it is a var node which tells us which * attribute to use for our scan key. * ---------------- */ varattno = ((Var *) rightop)->varattno; scanvar = RIGHT_OP; } else if (is_funcclause(rightop) && var_is_rel(lfirst(((Expr *) rightop)->args))) { /* ---------------- * if the rightop is a func node then it means * it identifies the value to place in our scan key. * Since functional indices have only one attribute * the attno must always be set to 1. * ---------------- */ if (scanvar == LEFT_OP) elog(ERROR, "ExecInitIndexScan: %s", "both left and right ops are rel-vars"); varattno = 1; scanvar = RIGHT_OP; } else if (IsA(rightop, Const)) { /* ---------------- * if the rightop is a const node then it means * it identifies the value to place in our scan key. * ---------------- */ run_keys[j] = NO_OP; scanvalue = ((Const *) rightop)->constvalue; } else if (IsA(rightop, Param)) { bool isnull; /* ---------------- * if the rightop is a Param node then it means * it identifies the value to place in our scan key. * ---------------- */ /* Life was so easy before ... subselects */ if (((Param *) rightop)->paramkind == PARAM_EXEC) { have_runtime_keys = true; run_keys[j] = RIGHT_OP; execParam = lappendi(execParam, ((Param *) rightop)->paramid); } else { scanvalue = ExecEvalParam((Param *) rightop, scanstate->cstate.cs_ExprContext, &isnull); if (isnull) flags |= SK_ISNULL; run_keys[j] = NO_OP; } } else { /* ---------------- * otherwise, the rightop contains information usable * at runtime to figure out the value to place in our * scan key. * ---------------- */ have_runtime_keys = true; run_keys[j] = RIGHT_OP; scanvalue = Int32GetDatum((int32) true); } /* ---------------- * now check that at least one op tells us the scan * attribute... * ---------------- */ if (scanvar == NO_OP) elog(ERROR, "ExecInitIndexScan: %s", "neither leftop nor rightop refer to scan relation"); /* ---------------- * initialize the scan key's fields appropriately * ---------------- */ ScanKeyEntryInitialize(&scan_keys[j], flags, varattno, /* attribute number to * scan */ (RegProcedure) opid, /* reg proc to use */ (Datum) scanvalue); /* constant */ } /* ---------------- * store the key information into our array. * ---------------- */ numScanKeys[i] = n_keys; scanKeys[i] = scan_keys; runtimeKeyInfo[i] = (Pointer) run_keys; } indexstate->iss_NumIndices = numIndices; if (ScanDirectionIsBackward(node->indxorderdir)) indexPtr = numIndices; indexstate->iss_IndexPtr = indexPtr; indexstate->iss_ScanKeys = scanKeys; indexstate->iss_NumScanKeys = numScanKeys; /* ---------------- * If all of our keys have the form (op var const) , then we have no * runtime keys so we store NULL in the runtime key info. * Otherwise runtime key info contains an array of pointers * (one for each index) to arrays of flags (one for each key) * which indicate that the qual needs to be evaluated at runtime. * -cim 10/24/89 * ---------------- */ if (have_runtime_keys) indexstate->iss_RuntimeKeyInfo = (Pointer) runtimeKeyInfo; else indexstate->iss_RuntimeKeyInfo = NULL; /* ---------------- * get the range table and direction information * from the execution state (these are needed to * open the relations). * ---------------- */ rangeTable = estate->es_range_table; direction = estate->es_direction; /* ---------------- * open the base relation * ---------------- */ relid = node->scan.scanrelid; rtentry = rt_fetch(relid, rangeTable); reloid = rtentry->relid; ExecOpenScanR(reloid, /* relation */ 0, /* nkeys */ (ScanKey) NULL, /* scan key */ 0, /* is index */ direction, /* scan direction */ estate->es_snapshot, /* */ ¤tRelation, /* return: rel desc */ (Pointer *) ¤tScanDesc); /* return: scan desc */ scanstate->css_currentRelation = currentRelation; scanstate->css_currentScanDesc = currentScanDesc; /* ---------------- * get the scan type from the relation descriptor. * ---------------- */ ExecAssignScanType(scanstate, RelationGetDescr(currentRelation)); ExecAssignResultTypeFromTL((Plan *) node, &scanstate->cstate); /* ---------------- * index scans don't have subtrees.. * ---------------- */ /* scanstate->ss_ProcOuterFlag = false; */ /* ---------------- * open the index relations and initialize * relation and scan descriptors. * ---------------- */ for (i = 0; i < numIndices; i++) { Oid indexOid; indexOid = (Oid) nthi(i, indxid); if (indexOid != 0) { ExecOpenScanR(indexOid, /* relation */ numScanKeys[i], /* nkeys */ scanKeys[i], /* scan key */ true, /* is index */ direction, /* scan direction */ estate->es_snapshot, &(relationDescs[i]), /* return: rel desc */ (Pointer *) &(scanDescs[i])); /* return: scan desc */ } } indexstate->iss_RelationDescs = relationDescs; indexstate->iss_ScanDescs = scanDescs; indexstate->cstate.cs_TupFromTlist = false; /* * if there are some PARAM_EXEC in skankeys then force index rescan on * first scan. */ ((Plan *) node)->chgParam = execParam; /* ---------------- * all done. * ---------------- */ return TRUE; } int ExecCountSlotsIndexScan(IndexScan *node) { return ExecCountSlotsNode(outerPlan((Plan *) node)) + ExecCountSlotsNode(innerPlan((Plan *) node)) + INDEXSCAN_NSLOTS; }