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a0185461dd
This commit changes index-only scans so that data is read directly from the index tuple without first generating a faux heap tuple. The only immediate benefit is that indexes on system columns (such as OID) can be used in index-only scans, but this is necessary infrastructure if we are ever to support index-only scans on expression indexes. The executor is now ready for that, though the planner still needs substantial work to recognize the possibility. To do this, Vars in index-only plan nodes have to refer to index columns not heap columns. I introduced a new special varno, INDEX_VAR, to mark such Vars to avoid confusion. (In passing, this commit renames the two existing special varnos to OUTER_VAR and INNER_VAR.) This allows ruleutils.c to handle them with logic similar to what we use for subplan reference Vars. Since index-only scans are now fundamentally different from regular indexscans so far as their expression subtrees are concerned, I also chose to change them to have their own plan node type (and hence, their own executor source file). |
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| .. | ||
| execdebug.h | ||
| execdesc.h | ||
| executor.h | ||
| functions.h | ||
| hashjoin.h | ||
| instrument.h | ||
| nodeAgg.h | ||
| nodeAppend.h | ||
| nodeBitmapAnd.h | ||
| nodeBitmapHeapscan.h | ||
| nodeBitmapIndexscan.h | ||
| nodeBitmapOr.h | ||
| nodeCtescan.h | ||
| nodeForeignscan.h | ||
| nodeFunctionscan.h | ||
| nodeGroup.h | ||
| nodeHash.h | ||
| nodeHashjoin.h | ||
| nodeIndexonlyscan.h | ||
| nodeIndexscan.h | ||
| nodeLimit.h | ||
| nodeLockRows.h | ||
| nodeMaterial.h | ||
| nodeMergeAppend.h | ||
| nodeMergejoin.h | ||
| nodeModifyTable.h | ||
| nodeNestloop.h | ||
| nodeRecursiveunion.h | ||
| nodeResult.h | ||
| nodeSeqscan.h | ||
| nodeSetOp.h | ||
| nodeSort.h | ||
| nodeSubplan.h | ||
| nodeSubqueryscan.h | ||
| nodeTidscan.h | ||
| nodeUnique.h | ||
| nodeValuesscan.h | ||
| nodeWindowAgg.h | ||
| nodeWorktablescan.h | ||
| spi.h | ||
| spi_priv.h | ||
| tstoreReceiver.h | ||
| tuptable.h | ||