diff options
Diffstat (limited to 'src/backend/executor/nodeIndexscan.c')
| -rw-r--r-- | src/backend/executor/nodeIndexscan.c | 61 |
1 files changed, 21 insertions, 40 deletions
diff --git a/src/backend/executor/nodeIndexscan.c b/src/backend/executor/nodeIndexscan.c index 0994dbf84ef..ad64c148241 100644 --- a/src/backend/executor/nodeIndexscan.c +++ b/src/backend/executor/nodeIndexscan.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/executor/nodeIndexscan.c,v 1.139 2010/02/26 02:00:42 momjian Exp $ + * $PostgreSQL: pgsql/src/backend/executor/nodeIndexscan.c,v 1.140 2010/07/12 17:01:05 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -17,7 +17,7 @@ * ExecIndexScan scans a relation using indices * ExecIndexNext using index to retrieve next tuple * ExecInitIndexScan creates and initializes state info. - * ExecIndexReScan rescans the indexed relation. + * ExecReScanIndexScan rescans the indexed relation. * ExecEndIndexScan releases all storage. * ExecIndexMarkPos marks scan position. * ExecIndexRestrPos restores scan position. @@ -141,7 +141,7 @@ ExecIndexScan(IndexScanState *node) * If we have runtime keys and they've not already been set up, do it now. */ if (node->iss_NumRuntimeKeys != 0 && !node->iss_RuntimeKeysReady) - ExecReScan((PlanState *) node, NULL); + ExecReScan((PlanState *) node); return ExecScan(&node->ss, (ExecScanAccessMtd) IndexNext, @@ -149,54 +149,35 @@ ExecIndexScan(IndexScanState *node) } /* ---------------------------------------------------------------- - * ExecIndexReScan(node) + * ExecReScanIndexScan(node) + * + * Recalculates the values of any scan keys whose value depends on + * information known at runtime, then rescans the indexed relation. * - * 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(IndexScanState *node, ExprContext *exprCtxt) +ExecReScanIndexScan(IndexScanState *node) { - ExprContext *econtext; - - econtext = node->iss_RuntimeContext; /* context for runtime keys */ - - if (econtext) - { - /* - * If we are being passed an outer tuple, save it for runtime key - * calc. We also need to link it into the "regular" per-tuple - * econtext, so it can be used during indexqualorig evaluations. - */ - if (exprCtxt != NULL) - { - ExprContext *stdecontext; - - econtext->ecxt_outertuple = exprCtxt->ecxt_outertuple; - stdecontext = node->ss.ps.ps_ExprContext; - stdecontext->ecxt_outertuple = exprCtxt->ecxt_outertuple; - } - - /* - * Reset the runtime-key context so we don't leak memory as each outer - * tuple is scanned. Note this assumes that we will recalculate *all* - * runtime keys on each call. - */ - ResetExprContext(econtext); - } - /* - * If we are doing runtime key calculations (ie, the index keys depend on - * data from an outer scan), compute the new key values + * If we are doing runtime key calculations (ie, any of the index key + * values weren't simple Consts), compute the new key values. But first, + * reset the context so we don't leak memory as each outer tuple is + * scanned. Note this assumes that we will recalculate *all* runtime keys + * on each call. */ if (node->iss_NumRuntimeKeys != 0) + { + ExprContext *econtext = node->iss_RuntimeContext; + + ResetExprContext(econtext); ExecIndexEvalRuntimeKeys(econtext, node->iss_RuntimeKeys, node->iss_NumRuntimeKeys); + } node->iss_RuntimeKeysReady = true; /* reset index scan */ @@ -229,11 +210,11 @@ ExecIndexEvalRuntimeKeys(ExprContext *econtext, /* * For each run-time key, extract the run-time expression and evaluate - * it with respect to the current outer tuple. We then stick the - * result into the proper scan key. + * it with respect to the current context. We then stick the result + * into the proper scan key. * * Note: the result of the eval could be a pass-by-ref value that's - * stored in the outer scan's tuple, not in + * stored in some outer scan's tuple, not in * econtext->ecxt_per_tuple_memory. We assume that the outer tuple * will stay put throughout our scan. If this is wrong, we could copy * the result into our context explicitly, but I think that's not |