database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-07-05 07:21:24 +03:00
Code Activity

Introduce traversalValue for SP-GiST scan

Browse Source 
During scan sometimes it would be very helpful to know some information about
parent node or all 	ancestor nodes. Right now reconstructedValue could be used
but it's not a right usage of it (range opclass uses that).

traversalValue is arbitrary piece of memory in separate MemoryContext while
reconstructedVale should have the same type as indexed column.

Subsequent patches for range opclass and quad4d tree will use it.

Author: Alexander Lebedev, Teodor Sigaev
This commit is contained in:
Teodor Sigaev
2016-03-30 18:29:28 +03:00
parent 3063e7a840
commit ccd6eb49a4
3 changed files with 37 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

18
src/backend/access/spgist/spgscan.c
View File

@ -30,6 +30,7 @@ typedef void (*storeRes_func) (SpGistScanOpaque so, ItemPointer heapPtr,
typedef struct ScanStackEntry
{
Datum reconstructedValue; /* value reconstructed from parent */
void *traversalValue; /* opclass-specific traverse value */
int level; /* level of items on this page */
ItemPointerData ptr; /* block and offset to scan from */
} ScanStackEntry;
@ -42,6 +43,9 @@ freeScanStackEntry(SpGistScanOpaque so, ScanStackEntry *stackEntry)
if (!so->state.attType.attbyval &&
DatumGetPointer(stackEntry->reconstructedValue) != NULL)
pfree(DatumGetPointer(stackEntry->reconstructedValue));
if (stackEntry->traversalValue)
pfree(stackEntry->traversalValue);
pfree(stackEntry);
}
@ -239,6 +243,7 @@ static bool
spgLeafTest(Relation index, SpGistScanOpaque so,
SpGistLeafTuple leafTuple, bool isnull,
int level, Datum reconstructedValue,
void *traversalValue,
Datum *leafValue, bool *recheck)
{
bool result;
@ -265,6 +270,7 @@ spgLeafTest(Relation index, SpGistScanOpaque so,
in.scankeys = so->keyData;
in.nkeys = so->numberOfKeys;
in.reconstructedValue = reconstructedValue;
in.traversalValue = traversalValue;
in.level = level;
in.returnData = so->want_itup;
in.leafDatum = leafDatum;
@ -365,6 +371,7 @@ redirect:
leafTuple, isnull,
stackEntry->level,
stackEntry->reconstructedValue,
stackEntry->traversalValue,
&leafValue,
&recheck))
{
@ -411,6 +418,7 @@ redirect:
leafTuple, isnull,
stackEntry->level,
stackEntry->reconstructedValue,
stackEntry->traversalValue,
&leafValue,
&recheck))
{
@ -456,6 +464,8 @@ redirect:
in.scankeys = so->keyData;
in.nkeys = so->numberOfKeys;
in.reconstructedValue = stackEntry->reconstructedValue;
in.traversalMemoryContext = oldCtx;
in.traversalValue = stackEntry->traversalValue;
in.level = stackEntry->level;
in.returnData = so->want_itup;
in.allTheSame = innerTuple->allTheSame;
@ -523,6 +533,14 @@ redirect:
else
newEntry->reconstructedValue = (Datum) 0;
/*
* Elements of out.traversalValues should be allocated in
* in.traversalMemoryContext, which is actually a long
* lived context of index scan.
*/
newEntry->traversalValue = (out.traversalValues) ?
out.traversalValues[i] : NULL;
so->scanStack = lcons(newEntry, so->scanStack);
}
}