4 files changed, 55 insertions, 10 deletions
diff --git a/src/include/catalog/catversion.h b/src/include/catalog/catversion.h
index 91feaec19e2..c34655308e0 100644
--- a/src/include/catalog/catversion.h
+++ b/src/include/catalog/catversion.h
@@ -37,7 +37,7 @@
  * Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: catversion.h,v 1.83 2001/06/16 18:59:31 tgl Exp $
+ * $Id: catversion.h,v 1.84 2001/06/19 22:39:12 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -53,6 +53,6 @@
  */
 
 /*							yyyymmddN */
-#define CATALOG_VERSION_NO	200106161
+#define CATALOG_VERSION_NO	200106191
 
 #endif
diff --git a/src/include/nodes/nodes.h b/src/include/nodes/nodes.h
index d62583c4d23..fe2d0357848 100644
--- a/src/include/nodes/nodes.h
+++ b/src/include/nodes/nodes.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: nodes.h,v 1.90 2001/06/09 23:21:55 petere Exp $
+ * $Id: nodes.h,v 1.91 2001/06/19 22:39:12 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -218,8 +218,8 @@ typedef enum NodeTag
 	T_RangeTblEntry,
 	T_SortClause,
 	T_GroupClause,
-	T_SubSelectXXX,				/* not used anymore; tag# available */
-	T_oldJoinExprXXX,			/* not used anymore; tag# available */
+	T_NullTest,
+	T_BooleanTest,
 	T_CaseExpr,
 	T_CaseWhen,
 	T_RowMarkXXX,				/* not used anymore; tag# available */
diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h
index fe2d1bb7ffe..43e64b6ad5f 100644
--- a/src/include/nodes/parsenodes.h
+++ b/src/include/nodes/parsenodes.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: parsenodes.h,v 1.131 2001/06/09 23:21:55 petere Exp $
+ * $Id: parsenodes.h,v 1.132 2001/06/19 22:39:12 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -983,9 +983,8 @@ typedef struct ParamNo
 typedef struct A_Expr
 {
 	NodeTag		type;
-	int			oper;			/* type of operation
-								 * {OP,OR,AND,NOT,ISNULL,NOTNULL} */
-	char	   *opname;			/* name of operator/function */
+	int			oper;			/* type of operation (OP,OR,AND,NOT) */
+	char	   *opname;			/* name of operator */
 	Node	   *lexpr;			/* left argument */
 	Node	   *rexpr;			/* right argument */
 } A_Expr;
@@ -1054,6 +1053,50 @@ typedef struct CaseWhen
 	Node	   *result;			/* substitution result */
 } CaseWhen;
 
+/* ----------------
+ * NullTest
+ *
+ * NullTest represents the operation of testing a value for NULLness.
+ * Currently, we only support scalar input values, but eventually a
+ * row-constructor input should be supported.
+ * The appropriate test is performed and returned as a boolean Datum.
+ * ----------------
+ */
+
+typedef enum NullTestType
+{
+	IS_NULL, IS_NOT_NULL
+} NullTestType;
+
+typedef struct NullTest
+{
+	NodeTag			type;
+	Node			*arg;			/* input expression */
+	NullTestType	nulltesttype;	/* IS NULL, IS NOT NULL */
+} NullTest;
+
+/* ----------------
+ * BooleanTest
+ *
+ * BooleanTest represents the operation of determining whether a boolean
+ * is TRUE, FALSE, or UNKNOWN (ie, NULL).  All six meaningful combinations
+ * are supported.  Note that a NULL input does *not* cause a NULL result.
+ * The appropriate test is performed and returned as a boolean Datum.
+ * ----------------
+ */
+
+typedef enum BoolTestType
+{
+	IS_TRUE, IS_NOT_TRUE, IS_FALSE, IS_NOT_FALSE, IS_UNKNOWN, IS_NOT_UNKNOWN
+} BoolTestType;
+
+typedef struct BooleanTest
+{
+	NodeTag			type;
+	Node			*arg;			/* input expression */
+	BoolTestType	booltesttype;	/* test type */
+} BooleanTest;
+
 /*
  * ColumnDef - column definition (used in various creates)
  *
diff --git a/src/include/parser/parse_coerce.h b/src/include/parser/parse_coerce.h
index f81a3be8307..1f508b1eae0 100644
--- a/src/include/parser/parse_coerce.h
+++ b/src/include/parser/parse_coerce.h
@@ -7,7 +7,7 @@
  * Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
  * Portions Copyright (c) 1994, Regents of the University of California
  *
- * $Id: parse_coerce.h,v 1.28 2001/05/22 16:37:17 petere Exp $
+ * $Id: parse_coerce.h,v 1.29 2001/06/19 22:39:12 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -136,6 +136,8 @@ extern Node *coerce_type(ParseState *pstate, Node *node, Oid inputTypeId,
 extern Node *coerce_type_typmod(ParseState *pstate, Node *node,
 				   Oid targetTypeId, int32 atttypmod);
 
+extern bool coerce_to_boolean(ParseState *pstate, Node **pnode);
+
 extern Oid	select_common_type(List *typeids, const char *context);
 extern Node *coerce_to_common_type(ParseState *pstate, Node *node,
 					  Oid targetTypeId,