SQL-language functions are now callable in ordinary fmgr contexts ...

for example, an SQL function can be used in a functional index.  (I make
no promises about speed, but it'll work ;-).)  Clean up and simplify
handling of functions returning sets.

3 files changed, 35 insertions, 5 deletions

diff --git a/src/include/nodes/execnodes.h b/src/include/nodes/execnodes.h
index 1ec14f4a969..9626dbf8b1c 100644
--- a/src/include/nodes/execnodes.h
+++ b/src/include/nodes/execnodes.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2000, PostgreSQL, Inc
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: execnodes.h,v 1.47 2000/08/22 04:06:22 tgl Exp $
+ * $Id: execnodes.h,v 1.48 2000/08/24 03:29:13 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -120,6 +120,31 @@ typedef struct ExprContext
 	List	   *ecxt_range_table;
 } ExprContext;
 
+/*
+ * Set-result status returned by ExecEvalExpr()
+ */
+typedef enum
+{
+	ExprSingleResult,			/* expression does not return a set */
+	ExprMultipleResult,			/* this result is an element of a set */
+	ExprEndResult				/* there are no more elements in the set */
+} ExprDoneCond;
+
+/*
+ * When calling a function that might return a set (multiple rows),
+ * a node of this type is passed as fcinfo->resultinfo to allow
+ * return status to be passed back.  A function returning set should
+ * raise an error if no such resultinfo is provided.
+ *
+ * XXX this mechanism is a quick hack and probably needs to be redesigned.
+ */
+typedef struct ReturnSetInfo
+{
+	NodeTag		type;
+	ExprDoneCond isDone;
+} ReturnSetInfo;
+
+
 /* ----------------
  *		ProjectionInfo node information
  *
diff --git a/src/include/nodes/nodes.h b/src/include/nodes/nodes.h
index f05e0a0e1c9..d825c8fe395 100644
--- a/src/include/nodes/nodes.h
+++ b/src/include/nodes/nodes.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2000, PostgreSQL, Inc
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: nodes.h,v 1.74 2000/08/11 23:46:54 tgl Exp $
+ * $Id: nodes.h,v 1.75 2000/08/24 03:29:13 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -227,7 +227,9 @@ typedef enum NodeTag
 	 * TAGS FOR FUNCTION-CALL CONTEXT AND RESULTINFO NODES (cf. fmgr.h)
 	 *---------------------
 	 */
-	T_TriggerData = 800			/* in commands/trigger.h */
+	T_TriggerData = 800,		/* in commands/trigger.h */
+	T_ReturnSetInfo				/* in nodes/execnodes.h */
+
 } NodeTag;
 
 /*
diff --git a/src/include/nodes/primnodes.h b/src/include/nodes/primnodes.h
index 1ad9a3d082a..0ef350687dc 100644
--- a/src/include/nodes/primnodes.h
+++ b/src/include/nodes/primnodes.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2000, PostgreSQL, Inc
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: primnodes.h,v 1.46 2000/08/08 15:42:59 tgl Exp $
+ * $Id: primnodes.h,v 1.47 2000/08/24 03:29:13 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -16,7 +16,10 @@
 
 #include "access/attnum.h"
 #include "nodes/pg_list.h"
-#include "utils/fcache.h"
+
+/* FunctionCache is declared in utils/fcache.h */
+typedef struct FunctionCache *FunctionCachePtr;
+
 
 /* ----------------------------------------------------------------
  *						node definitions