!3753 索引扫描算子优化

Merge pull request !3753 from yyl/7-11-index

src/include/executor/tuptable.h

@@ -196,7 +196,33 @@ extern TupleTableSlot* ExecStoreDataRowTuple(
 #endif
 extern TupleTableSlot* ExecClearTuple(TupleTableSlot* slot);
 extern void ExecClearMutilTuple(List* slots);
-extern TupleTableSlot* ExecStoreVirtualTuple(TupleTableSlot* slot);
+
+/* --------------------------------
+ *		ExecStoreVirtualTuple
+ *			Mark a slot as containing a virtual tuple.
+ *
+ * The protocol for loading a slot with virtual tuple data is:
+ *		* Call ExecClearTuple to mark the slot empty.
+ *		* Store data into the Datum/isnull arrays.
+ *		* Call ExecStoreVirtualTuple to mark the slot valid.
+ * This is a bit unclean but it avoids one round of data copying.
+ * --------------------------------
+ */
+inline TupleTableSlot* ExecStoreVirtualTuple(TupleTableSlot* slot)
+{
+    /*
+     * sanity checks
+     */
+    Assert(slot != NULL);
+    Assert(slot->tts_tupleDescriptor != NULL);
+    Assert(TTS_EMPTY(slot));
+
+    slot->tts_flags &= ~TTS_FLAG_EMPTY;
+    slot->tts_nvalid = slot->tts_tupleDescriptor->natts;
+
+    return slot;
+}
+
 extern TupleTableSlot* ExecStoreAllNullTuple(TupleTableSlot* slot);
 extern HeapTuple ExecCopySlotTuple(TupleTableSlot* slot);
 extern MinimalTuple ExecCopySlotMinimalTuple(TupleTableSlot* slot, bool need_transform_anyarray = false);