Reimplementation of UNION/INTERSECT/EXCEPT. INTERSECT/EXCEPT now meet the

SQL92 semantics, including support for ALL option.  All three can be used
in subqueries and views.  DISTINCT and ORDER BY work now in views, too.
This rewrite fixes many problems with cross-datatype UNIONs and INSERT/SELECT
where the SELECT yields different datatypes than the INSERT needs.  I did
that by making UNION subqueries and SELECT in INSERT be treated like
subselects-in-FROM, thereby allowing an extra level of targetlist where the
datatype conversions can be inserted safely.
INITDB NEEDED!

1 files changed, 45 insertions, 20 deletions

diff --git a/src/backend/nodes/readfuncs.c b/src/backend/nodes/readfuncs.c
index da0ba22684f..57174bfb60e 100644
--- a/src/backend/nodes/readfuncs.c
+++ b/src/backend/nodes/readfuncs.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/nodes/readfuncs.c,v 1.97 2000/09/29 18:21:29 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/nodes/readfuncs.c,v 1.98 2000/10/05 19:11:27 tgl Exp $
  *
  * NOTES
  *	  Most of the read functions for plan nodes are tested. (In fact, they
@@ -109,10 +109,6 @@ _readQuery()
 	token = lsptok(NULL, &length);		/* get isTemp */
 	local_node->isTemp = (token[0] == 't') ? true : false;
 
-	token = lsptok(NULL, &length);		/* skip :unionall */
-	token = lsptok(NULL, &length);		/* get unionall */
-	local_node->unionall = (token[0] == 't') ? true : false;
-
 	token = lsptok(NULL, &length);		/* skip the :hasAggs */
 	token = lsptok(NULL, &length);		/* get hasAggs */
 	local_node->hasAggs = (token[0] == 't') ? true : false;
@@ -127,17 +123,11 @@ _readQuery()
 	token = lsptok(NULL, &length);		/* skip :jointree */
 	local_node->jointree = nodeRead(true);
 
-	token = lsptok(NULL, &length);		/* skip :targetlist */
-	local_node->targetList = nodeRead(true);
-
 	token = lsptok(NULL, &length);		/* skip :rowMarks */
 	local_node->rowMarks = toIntList(nodeRead(true));
 
-	token = lsptok(NULL, &length);		/* skip :distinctClause */
-	local_node->distinctClause = nodeRead(true);
-
-	token = lsptok(NULL, &length);		/* skip :sortClause */
-	local_node->sortClause = nodeRead(true);
+	token = lsptok(NULL, &length);		/* skip :targetlist */
+	local_node->targetList = nodeRead(true);
 
 	token = lsptok(NULL, &length);		/* skip :groupClause */
 	local_node->groupClause = nodeRead(true);
@@ -145,11 +135,11 @@ _readQuery()
 	token = lsptok(NULL, &length);		/* skip :havingQual */
 	local_node->havingQual = nodeRead(true);
 
-	token = lsptok(NULL, &length);		/* skip :intersectClause */
-	local_node->intersectClause = nodeRead(true);
+	token = lsptok(NULL, &length);		/* skip :distinctClause */
+	local_node->distinctClause = nodeRead(true);
 
-	token = lsptok(NULL, &length);		/* skip :unionClause */
-	local_node->unionClause = nodeRead(true);
+	token = lsptok(NULL, &length);		/* skip :sortClause */
+	local_node->sortClause = nodeRead(true);
 
 	token = lsptok(NULL, &length);		/* skip :limitOffset */
 	local_node->limitOffset = nodeRead(true);
@@ -157,6 +147,9 @@ _readQuery()
 	token = lsptok(NULL, &length);		/* skip :limitCount */
 	local_node->limitCount = nodeRead(true);
 
+	token = lsptok(NULL, &length);		/* skip :setOperations */
+	local_node->setOperations = nodeRead(true);
+
 	return local_node;
 }
 
@@ -209,6 +202,39 @@ _readGroupClause()
 }
 
 /* ----------------
+ *		_readSetOperationStmt
+ * ----------------
+ */
+static SetOperationStmt *
+_readSetOperationStmt()
+{
+	SetOperationStmt *local_node;
+	char	   *token;
+	int			length;
+
+	local_node = makeNode(SetOperationStmt);
+
+	token = lsptok(NULL, &length);		/* eat :op */
+	token = lsptok(NULL, &length);		/* get op */
+	local_node->op = (SetOperation) atoi(token);
+
+	token = lsptok(NULL, &length);		/* eat :all */
+	token = lsptok(NULL, &length);		/* get all */
+	local_node->all = (token[0] == 't') ? true : false;
+
+	token = lsptok(NULL, &length);		/* eat :larg */
+	local_node->larg = nodeRead(true);	/* get larg */
+
+	token = lsptok(NULL, &length);		/* eat :rarg */
+	local_node->rarg = nodeRead(true);	/* get rarg */
+
+	token = lsptok(NULL, &length);		/* eat :colTypes */
+	local_node->colTypes = toIntList(nodeRead(true));
+
+	return local_node;
+}
+
+/* ----------------
  *		_getPlan
  * ----------------
  */
@@ -322,9 +348,6 @@ _readAppend()
 	token = lsptok(NULL, &length);		/* eat :appendplans */
 	local_node->appendplans = nodeRead(true);	/* now read it */
 
-	token = lsptok(NULL, &length);		/* eat :unionrtables */
-	local_node->unionrtables = nodeRead(true);	/* now read it */
-
 	token = lsptok(NULL, &length);		/* eat :inheritrelid */
 	token = lsptok(NULL, &length);		/* get inheritrelid */
 	local_node->inheritrelid = strtoul(token, NULL, 10);
@@ -1995,6 +2018,8 @@ parsePlanString(void)
 		return_value = _readSortClause();
 	else if (length == 11 && strncmp(token, "GROUPCLAUSE", length) == 0)
 		return_value = _readGroupClause();
+	else if (length == 16 && strncmp(token, "SETOPERATIONSTMT", length) == 0)
+		return_value = _readSetOperationStmt();
 	else if (length == 4 && strncmp(token, "CASE", length) == 0)
 		return_value = _readCaseExpr();
 	else if (length == 4 && strncmp(token, "WHEN", length) == 0)