Add comments on some MinimalTupleSlots methods usage

akorotkov · akorotkov · commit 10baee0c95d1 · 2024-03-26T01:53:34.000+02:00
Discussion: https://postgr.es/m/CALT9ZEHNeagO5PLb4Nv9J_ZaCtp%2BArdVmbSLc0RHUzx_RPAa4w%40mail.gmail.com Author: Pavel Borisov
diff --git a/src/backend/executor/execTuples.c b/src/backend/executor/execTuples.c
@@ -549,6 +549,10 @@ tts_minimal_getsomeattrs(TupleTableSlot *slot, int natts)
 	slot_deform_heap_tuple(slot, mslot->tuple, &mslot->off, natts);
 }
 
+/*
+ * MinimalTupleTableSlots never provide system attributes. We generally
+ * shouldn't get here, but provide a user-friendly message if we do.
+ */
 static Datum
 tts_minimal_getsysattr(TupleTableSlot *slot, int attnum, bool *isnull)
 {
@@ -561,6 +565,11 @@ tts_minimal_getsysattr(TupleTableSlot *slot, int attnum, bool *isnull)
 	return 0;					/* silence compiler warnings */
 }
 
+/*
+ * Within MinimalTuple abstraction transaction information is unavailable.
+ * We generally shouldn't get here, but provide a user-friendly message if
+ * we do.
+ */
 static bool
 tts_minimal_is_current_xact_tuple(TupleTableSlot *slot)
 {

Original file line number	Diff line number	Diff line change
`@@ -549,6 +549,10 @@ tts_minimal_getsomeattrs(TupleTableSlot *slot, int natts)`
`549`	`549`	`slot_deform_heap_tuple(slot, mslot->tuple, &mslot->off, natts);`
`550`	`550`	`}`
`551`	`551`
	`552`	`+/*`
	`553`	`+ * MinimalTupleTableSlots never provide system attributes. We generally`
	`554`	`+ * shouldn't get here, but provide a user-friendly message if we do.`
	`555`	`+ */`
`552`	`556`	`static Datum`
`553`	`557`	`tts_minimal_getsysattr(TupleTableSlot slot, int attnum, bool isnull)`
`554`	`558`	`{`
`@@ -561,6 +565,11 @@ tts_minimal_getsysattr(TupleTableSlot slot, int attnum, bool isnull)`
`561`	`565`	`return 0; /* silence compiler warnings */`
`562`	`566`	`}`
`563`	`567`
	`568`	`+/*`
	`569`	`+ * Within MinimalTuple abstraction transaction information is unavailable.`
	`570`	`+ * We generally shouldn't get here, but provide a user-friendly message if`
	`571`	`+ * we do.`
	`572`	`+ */`
`564`	`573`	`static bool`
`565`	`574`	`tts_minimal_is_current_xact_tuple(TupleTableSlot *slot)`
`566`	`575`	`{`