diff options
Diffstat (limited to 'src/backend/executor/nodeIndexonlyscan.c')
| -rw-r--r-- | src/backend/executor/nodeIndexonlyscan.c | 95 |
1 files changed, 88 insertions, 7 deletions
diff --git a/src/backend/executor/nodeIndexonlyscan.c b/src/backend/executor/nodeIndexonlyscan.c index 0b43a9b..45d1a67 100644 --- a/src/backend/executor/nodeIndexonlyscan.c +++ b/src/backend/executor/nodeIndexonlyscan.c @@ -35,19 +35,21 @@ #include "access/tableam.h" #include "access/tupdesc.h" #include "access/visibilitymap.h" +#include "catalog/pg_type.h" #include "executor/execdebug.h" #include "executor/nodeIndexonlyscan.h" #include "executor/nodeIndexscan.h" #include "miscadmin.h" #include "storage/bufmgr.h" #include "storage/predicate.h" +#include "utils/builtins.h" #include "utils/memutils.h" #include "utils/rel.h" static TupleTableSlot *IndexOnlyNext(IndexOnlyScanState *node); -static void StoreIndexTuple(TupleTableSlot *slot, IndexTuple itup, - TupleDesc itupdesc); +static void StoreIndexTuple(IndexOnlyScanState *node, TupleTableSlot *slot, + IndexTuple itup, TupleDesc itupdesc); /* ---------------------------------------------------------------- @@ -206,7 +208,7 @@ IndexOnlyNext(IndexOnlyScanState *node) ExecForceStoreHeapTuple(scandesc->xs_hitup, slot, false); } else if (scandesc->xs_itup) - StoreIndexTuple(slot, scandesc->xs_itup, scandesc->xs_itupdesc); + StoreIndexTuple(node, slot, scandesc->xs_itup, scandesc->xs_itupdesc); else elog(ERROR, "no data returned for index-only scan"); @@ -264,7 +266,8 @@ IndexOnlyNext(IndexOnlyScanState *node) * right now we don't need it elsewhere. */ static void -StoreIndexTuple(TupleTableSlot *slot, IndexTuple itup, TupleDesc itupdesc) +StoreIndexTuple(IndexOnlyScanState *node, TupleTableSlot *slot, + IndexTuple itup, TupleDesc itupdesc) { /* * Note: we must use the tupdesc supplied by the AM in index_deform_tuple, @@ -277,6 +280,37 @@ StoreIndexTuple(TupleTableSlot *slot, IndexTuple itup, TupleDesc itupdesc) ExecClearTuple(slot); index_deform_tuple(itup, itupdesc, slot->tts_values, slot->tts_isnull); + + /* + * Copy all name columns stored as cstrings back into a NAMEDATALEN byte + * sized allocation. We mark this branch as unlikely as generally "name" + * is used only for the system catalogs and this would have to be a user + * query running on those or some other user table with an index on a name + * column. + */ + if (unlikely(node->ioss_NameCStringAttNums != NULL)) + { + int attcount = node->ioss_NameCStringCount; + + for (int idx = 0; idx < attcount; idx++) + { + int attnum = node->ioss_NameCStringAttNums[idx]; + Name name; + + /* skip null Datums */ + if (slot->tts_isnull[attnum]) + continue; + + /* allocate the NAMEDATALEN and copy the datum into that memory */ + name = (Name) MemoryContextAlloc(node->ss.ps.ps_ExprContext->ecxt_per_tuple_memory, + NAMEDATALEN); + + /* use namestrcpy to zero-pad all trailing bytes */ + namestrcpy(name, DatumGetCString(slot->tts_values[attnum])); + slot->tts_values[attnum] = NameGetDatum(name); + } + } + ExecStoreVirtualTuple(slot); } @@ -490,8 +524,11 @@ ExecInitIndexOnlyScan(IndexOnlyScan *node, EState *estate, int eflags) { IndexOnlyScanState *indexstate; Relation currentRelation; + Relation indexRelation; LOCKMODE lockmode; TupleDesc tupDesc; + int indnkeyatts; + int namecount; /* * create state structure @@ -564,7 +601,8 @@ ExecInitIndexOnlyScan(IndexOnlyScan *node, EState *estate, int eflags) /* Open the index relation. */ lockmode = exec_rt_fetch(node->scan.scanrelid, estate)->rellockmode; - indexstate->ioss_RelationDesc = index_open(node->indexid, lockmode); + indexRelation = index_open(node->indexid, lockmode); + indexstate->ioss_RelationDesc = indexRelation; /* * Initialize index-specific scan state @@ -577,7 +615,7 @@ ExecInitIndexOnlyScan(IndexOnlyScan *node, EState *estate, int eflags) * build the index scan keys from the index qualification */ ExecIndexBuildScanKeys((PlanState *) indexstate, - indexstate->ioss_RelationDesc, + indexRelation, node->indexqual, false, &indexstate->ioss_ScanKeys, @@ -591,7 +629,7 @@ ExecInitIndexOnlyScan(IndexOnlyScan *node, EState *estate, int eflags) * any ORDER BY exprs have to be turned into scankeys in the same way */ ExecIndexBuildScanKeys((PlanState *) indexstate, - indexstate->ioss_RelationDesc, + indexRelation, node->indexorderby, true, &indexstate->ioss_OrderByKeys, @@ -620,6 +658,49 @@ ExecInitIndexOnlyScan(IndexOnlyScan *node, EState *estate, int eflags) indexstate->ioss_RuntimeContext = NULL; } + indexstate->ioss_NameCStringAttNums = NULL; + indnkeyatts = indexRelation->rd_index->indnkeyatts; + namecount = 0; + + /* + * The "name" type for btree uses text_ops which results in storing + * cstrings in the indexed keys rather than names. Here we detect that in + * a generic way in case other index AMs want to do the same optimization. + * Check for opclasses with an opcintype of NAMEOID and an index tuple + * descriptor with CSTRINGOID. If any of these are found, create an array + * marking the index attribute number of each of them. StoreIndexTuple() + * handles copying the name Datums into a NAMEDATALEN-byte allocation. + */ + + /* First, count the number of such index keys */ + for (int attnum = 0; attnum < indnkeyatts; attnum++) + { + if (indexRelation->rd_att->attrs[attnum].atttypid == CSTRINGOID && + indexRelation->rd_opcintype[attnum] == NAMEOID) + namecount++; + } + + if (namecount > 0) + { + int idx = 0; + + /* + * Now create an array to mark the attribute numbers of the keys that + * need to be converted from cstring to name. + */ + indexstate->ioss_NameCStringAttNums = (AttrNumber *) + palloc(sizeof(AttrNumber) * namecount); + + for (int attnum = 0; attnum < indnkeyatts; attnum++) + { + if (indexRelation->rd_att->attrs[attnum].atttypid == CSTRINGOID && + indexRelation->rd_opcintype[attnum] == NAMEOID) + indexstate->ioss_NameCStringAttNums[idx++] = (AttrNumber) attnum; + } + } + + indexstate->ioss_NameCStringCount = namecount; + /* * all done. */ |