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-rw-r--r--src/backend/executor/nodeIndexonlyscan.c95
-rw-r--r--src/include/catalog/pg_opclass.dat7
-rw-r--r--src/include/nodes/execnodes.h4
-rw-r--r--src/test/regress/expected/index_including.out25
-rw-r--r--src/test/regress/sql/index_including.sql19
5 files changed, 141 insertions, 9 deletions
diff --git a/src/backend/executor/nodeIndexonlyscan.c b/src/backend/executor/nodeIndexonlyscan.c
index 661971e7070..bb1fd5d15da 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);
/* ----------------------------------------------------------------
@@ -208,7 +210,7 @@ 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");
@@ -266,7 +268,8 @@ 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,
@@ -279,6 +282,37 @@ 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);
}
@@ -492,8 +526,11 @@ ExecInitIndexOnlyScan(IndexOnlyScan *node, EState *estate, int eflags)
{
IndexOnlyScanState *indexstate;
Relation currentRelation;
+ Relation indexRelation;
LOCKMODE lockmode;
TupleDesc tupDesc;
+ int indnkeyatts;
+ int namecount;
/*
* create state structure
@@ -566,7 +603,8 @@ 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
@@ -579,7 +617,7 @@ 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,
@@ -593,7 +631,7 @@ 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,
@@ -622,6 +660,49 @@ 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.
*/
diff --git a/src/include/catalog/pg_opclass.dat b/src/include/catalog/pg_opclass.dat
index f2342bb328c..8e5a259684e 100644
--- a/src/include/catalog/pg_opclass.dat
+++ b/src/include/catalog/pg_opclass.dat
@@ -91,8 +91,11 @@
# Here's an ugly little hack to save space in the system catalog indexes.
# btree doesn't ordinarily allow a storage type different from input type;
# but cstring and name are the same thing except for trailing padding,
-# and we can safely omit that within an index entry. So we declare the
-# btree opclass for name as using cstring storage type.
+# so we choose to omit that within an index entry. Here we declare the
+# btree opclass for name as using cstring storage type. This does require
+# that we pad the cstring out with the full NAMEDATALEN bytes when performing
+# index-only scans. See corresponding hacks in ExecInitIndexOnlyScan() and
+# StoreIndexTuple().
{ opcmethod => 'btree', opcname => 'name_ops', opcfamily => 'btree/text_ops',
opcintype => 'name', opckeytype => 'cstring' },
diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h
index caf0d41f0bb..d05ec67231f 100644
--- a/src/include/nodes/execnodes.h
+++ b/src/include/nodes/execnodes.h
@@ -1484,6 +1484,8 @@ typedef struct IndexScanState
* TableSlot slot for holding tuples fetched from the table
* VMBuffer buffer in use for visibility map testing, if any
* PscanLen size of parallel index-only scan descriptor
+ * NameCStringAttNums attnums of name typed columns to pad to NAMEDATALEN
+ * NameCStringCount number of elements in the NameCStringAttNums array
* ----------------
*/
typedef struct IndexOnlyScanState
@@ -1503,6 +1505,8 @@ typedef struct IndexOnlyScanState
TupleTableSlot *ioss_TableSlot;
Buffer ioss_VMBuffer;
Size ioss_PscanLen;
+ AttrNumber *ioss_NameCStringAttNums;
+ int ioss_NameCStringCount;
} IndexOnlyScanState;
/* ----------------
diff --git a/src/test/regress/expected/index_including.out b/src/test/regress/expected/index_including.out
index 8e5d53e712a..4aacf355821 100644
--- a/src/test/regress/expected/index_including.out
+++ b/src/test/regress/expected/index_including.out
@@ -399,3 +399,28 @@ Indexes:
"tbl_c1_c2_c3_c4_key" UNIQUE CONSTRAINT, btree (c1, c2) INCLUDE (c3, c4)
DROP TABLE tbl;
+/*
+ * 10. Test coverage for names stored as cstrings in indexes
+ */
+CREATE TABLE nametbl (c1 int, c2 name, c3 float);
+CREATE INDEX nametbl_c1_c2_idx ON nametbl (c2, c1) INCLUDE (c3);
+INSERT INTO nametbl VALUES(1, 'two', 3.0);
+VACUUM nametbl;
+SET enable_seqscan = 0;
+-- Ensure we get an index only scan plan
+EXPLAIN (COSTS OFF) SELECT c2, c1, c3 FROM nametbl WHERE c2 = 'two' AND c1 = 1;
+ QUERY PLAN
+----------------------------------------------------
+ Index Only Scan using nametbl_c1_c2_idx on nametbl
+ Index Cond: ((c2 = 'two'::name) AND (c1 = 1))
+(2 rows)
+
+-- Validate the results look sane
+SELECT c2, c1, c3 FROM nametbl WHERE c2 = 'two' AND c1 = 1;
+ c2 | c1 | c3
+-----+----+----
+ two | 1 | 3
+(1 row)
+
+RESET enable_seqscan;
+DROP TABLE nametbl;
diff --git a/src/test/regress/sql/index_including.sql b/src/test/regress/sql/index_including.sql
index 7e517483adf..880f4bbc421 100644
--- a/src/test/regress/sql/index_including.sql
+++ b/src/test/regress/sql/index_including.sql
@@ -217,3 +217,22 @@ ALTER TABLE tbl ALTER c1 TYPE bigint;
ALTER TABLE tbl ALTER c3 TYPE bigint;
\d tbl
DROP TABLE tbl;
+
+/*
+ * 10. Test coverage for names stored as cstrings in indexes
+ */
+CREATE TABLE nametbl (c1 int, c2 name, c3 float);
+CREATE INDEX nametbl_c1_c2_idx ON nametbl (c2, c1) INCLUDE (c3);
+INSERT INTO nametbl VALUES(1, 'two', 3.0);
+VACUUM nametbl;
+SET enable_seqscan = 0;
+
+-- Ensure we get an index only scan plan
+EXPLAIN (COSTS OFF) SELECT c2, c1, c3 FROM nametbl WHERE c2 = 'two' AND c1 = 1;
+
+-- Validate the results look sane
+SELECT c2, c1, c3 FROM nametbl WHERE c2 = 'two' AND c1 = 1;
+
+RESET enable_seqscan;
+
+DROP TABLE nametbl; \ No newline at end of file
generated by cgit v1.2.3 (git 2.25.1) at 2025-05-19 11:54:25 +0000