Remove 'func_tlist' from Func expression nodes, likewise 'param_tlist'

from Param nodes, per discussion a few days ago on pghackers.  Add new
expression node type FieldSelect that implements the functionality where
it's actually needed.  Clean up some other unused fields in Func nodes
as well.
NOTE: initdb forced due to change in stored expression trees for rules.

1 files changed, 37 insertions, 56 deletions

diff --git a/src/backend/executor/execQual.c b/src/backend/executor/execQual.c
index a445a57d9cf..6e934a17725 100644
--- a/src/backend/executor/execQual.c
+++ b/src/backend/executor/execQual.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/executor/execQual.c,v 1.76 2000/07/23 01:35:58 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/executor/execQual.c,v 1.77 2000/08/08 15:41:22 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -294,8 +294,6 @@ ExecEvalVar(Var *variable, ExprContext *econtext, bool *isNull)
 	AttrNumber	attnum;
 	HeapTuple	heapTuple;
 	TupleDesc	tuple_type;
-	bool		byval;
-	int16		len;
 
 	/*
 	 * get the slot we want
@@ -363,36 +361,6 @@ ExecEvalVar(Var *variable, ExprContext *econtext, bool *isNull)
 						  tuple_type,	/* tuple descriptor of tuple */
 						  isNull);		/* return: is attribute null? */
 
-	/*
-	 * return null if att is null
-	 */
-	if (*isNull)
-		return (Datum) 0;
-
-	/*
-	 * get length and type information.. ??? what should we do about
-	 * variable length attributes - variable length attributes have their
-	 * length stored in the first 4 bytes of the memory pointed to by the
-	 * returned value.. If we can determine that the type is a variable
-	 * length type, we can do the right thing. -cim 9/15/89
-	 */
-	if (attnum < 0)
-	{
-
-		/*
-		 * If this is a pseudo-att, we get the type and fake the length.
-		 * There ought to be a routine to return the real lengths, so
-		 * we'll mark this one ... XXX -mao
-		 */
-		len = heap_sysattrlen(attnum);	/* XXX see -mao above */
-		byval = heap_sysattrbyval(attnum);		/* XXX see -mao above */
-	}
-	else
-	{
-		len = tuple_type->attrs[attnum - 1]->attlen;
-		byval = tuple_type->attrs[attnum - 1]->attbyval ? true : false;
-	}
-
 	return result;
 }
 
@@ -519,25 +487,7 @@ ExecEvalParam(Param *expression, ExprContext *econtext, bool *isNull)
 	/*
 	 * return the value.
 	 */
-	if (paramList->isnull)
-	{
-		*isNull = true;
-		return (Datum) 0;
-	}
-
-	if (expression->param_tlist != NIL)
-	{
-		HeapTuple	tup;
-		Datum		value;
-		List	   *tlist = expression->param_tlist;
-		TargetEntry *tle = (TargetEntry *) lfirst(tlist);
-		TupleTableSlot *slot = (TupleTableSlot *) paramList->value;
-
-		tup = slot->val;
-		value = ProjectAttribute(slot->ttc_tupleDescriptor,
-								 tle, tup, isNull);
-		return value;
-	}
+	*isNull = paramList->isnull;
 	return paramList->value;
 }
 
@@ -686,7 +636,6 @@ ExecMakeFunctionResult(Node *node,
 {
 	FunctionCallInfoData	fcinfo;
 	FunctionCachePtr		fcache;
-	List				   *ftlist;
 	bool					funcisset;
 	Datum					result;
 	bool					argDone;
@@ -702,13 +651,11 @@ ExecMakeFunctionResult(Node *node,
 	if (IsA(node, Func))
 	{
 		fcache = ((Func *) node)->func_fcache;
-		ftlist = ((Func *) node)->func_tlist;
 		funcisset = (((Func *) node)->funcid == F_SETEVAL);
 	}
 	else
 	{
 		fcache = ((Oper *) node)->op_fcache;
-		ftlist = NIL;
 		funcisset = false;
 	}
 
@@ -822,7 +769,7 @@ ExecMakeFunctionResult(Node *node,
 
 			if (callit)
 			{
-				result = postquel_function(&fcinfo, fcache, ftlist, isDone);
+				result = postquel_function(&fcinfo, fcache, isDone);
 				*isNull = fcinfo.isnull;
 			}
 			else
@@ -1215,6 +1162,34 @@ ExecEvalCase(CaseExpr *caseExpr, ExprContext *econtext, bool *isNull)
 }
 
 /* ----------------------------------------------------------------
+ *		ExecEvalFieldSelect
+ *
+ *		Evaluate a FieldSelect node.
+ * ----------------------------------------------------------------
+ */
+static Datum
+ExecEvalFieldSelect(FieldSelect *fselect,
+					ExprContext *econtext,
+					bool *isNull,
+					bool *isDone)
+{
+	Datum			result;
+	TupleTableSlot *resSlot;
+
+	result = ExecEvalExpr(fselect->arg, econtext, isNull, isDone);
+	if (*isNull)
+		return result;
+	/* XXX what about isDone? */
+	resSlot = (TupleTableSlot *) DatumGetPointer(result);
+	Assert(resSlot != NULL && IsA(resSlot, TupleTableSlot));
+	result = heap_getattr(resSlot->val,
+						  fselect->fieldnum,
+						  resSlot->ttc_tupleDescriptor,
+						  isNull);
+	return result;
+}
+
+/* ----------------------------------------------------------------
  *		ExecEvalExpr
  *
  *		Recursively evaluate a targetlist or qualification expression.
@@ -1319,6 +1294,12 @@ ExecEvalExpr(Node *expression,
 				}
 				break;
 			}
+		case T_FieldSelect:
+			retDatum = ExecEvalFieldSelect((FieldSelect *) expression,
+										   econtext,
+										   isNull,
+										   isDone);
+			break;
 		case T_RelabelType:
 			retDatum = ExecEvalExpr(((RelabelType *) expression)->arg,
 									econtext,