--- pool_proto_modules.h	2010-08-26 18:23:06.000000000 +0900
+++ pool_proto_modules.h	2010-09-27 11:01:57.000000000 +0900
@@ -1,7 +1,7 @@
 /* -*-pgsql-c-*- */
 /*
  *
- * $Header: /cvsroot/pgpool/pgpool-II/pool_proto_modules.h,v 1.23 2010/08/26 09:23:06 kitagawa Exp $
+ * $Header: /cvsroot/pgpool/pgpool-II/pool_proto_modules.h,v 1.24 2010/09/27 02:01:57 kitagawa Exp $
  *
  * pgpool: a language independent connection pool server for PostgreSQL 
  * written by Tatsuo Ishii
@@ -35,6 +35,7 @@
 #include "pool_session_context.h"
 
 #define SPECIFIED_ERROR 1
+#define POOL_DUMMY_QUERY "DELETE FROM foo WHERE col = 'pgpool: unable to parse the query'"
 #define POOL_ERROR_QUERY "send invalid query from pgpool to abort transaction"
 
 extern char *copy_table;  /* copy table name */
--- pool_proto_modules.c	2010-08-30 12:55:58.000000000 +0900
+++ pool_proto_modules.c	2010-09-29 15:02:07.000000000 +0900
@@ -1,6 +1,6 @@
 /* -*-pgsql-c-*- */
 /*
- * $Header: /cvsroot/pgpool/pgpool-II/pool_proto_modules.c,v 1.85 2010/08/30 03:55:58 kitagawa Exp $
+ * $Header: /cvsroot/pgpool/pgpool-II/pool_proto_modules.c,v 1.86 2010/09/27 02:01:57 kitagawa Exp $
  * 
  * pgpool: a language independent connection pool server for PostgreSQL 
  * written by Tatsuo Ishii
@@ -164,10 +164,8 @@
 		 * The command will be sent to all backends in replication mode
 		 * or master/primary in master/slave mode.
 		 */
-		char *p = "DELETE FROM foo WHERE col = 'pgpool: unable to parse the query'";
-
 		pool_log("SimpleQuery: Unable to parse the query: %s", contents);
-		parse_tree_list = raw_parser(p);
+		parse_tree_list = raw_parser(POOL_DUMMY_QUERY);
 	}
 
 	if (parse_tree_list != NIL)
@@ -615,13 +613,25 @@
 	old_context = pool_memory;
 	pool_memory = query_context->memory_context;
 
+	/* parse SQL string */
 	parse_tree_list = raw_parser(stmt);
+
 	if (parse_tree_list == NIL)
 	{
-		/* free_parser(); */
-		;
+		/*
+		 * Unable to parse the query. Probably syntax error or the
+		 * query is too new and our parser cannot understand. Treat as
+		 * if it were an DELETE command. Note that the DELETE command
+		 * does not execute, instead the original query will be sent
+		 * to backends, which may or may not cause an actual syntax errors.
+		 * The command will be sent to all backends in replication mode
+		 * or master/primary in master/slave mode.
+		 */
+		pool_log("Parse: Unable to parse the query: %s", contents);
+		parse_tree_list = raw_parser(POOL_DUMMY_QUERY);
 	}
-	else
+
+	if (parse_tree_list != NIL)
 	{
 		/* Save last query string for logging purpose */
 		snprintf(query_string_buffer, sizeof(query_string_buffer), "Parse: %s", stmt);
@@ -968,6 +978,7 @@
 	return POOL_CONTINUE;
 }
 
+
 POOL_STATUS Close(POOL_CONNECTION *frontend, POOL_CONNECTION_POOL *backend,
 				  int len, char *contents)
 {
@@ -995,6 +1006,7 @@
 		}
 
 		session_context->pending_pstmt = pstmt;
+		query_context = pstmt->qctxt;
 	}
 	/* Portal */
 	else if (*contents == 'P')
@@ -1007,6 +1019,7 @@
 		}
 
 		session_context->pending_portal = portal;
+		query_context = portal->qctxt;
 	}
 	else
 	{
@@ -1014,15 +1027,14 @@
 		return POOL_END;
 	}
 
-	query_context = pstmt->qctxt;
 	if (query_context == NULL)
 	{
 		pool_error("Close: cannot get query context");
 		return POOL_END;
 	}
 
-	pool_where_to_send(query_context, query_context->original_query,
-					   query_context->parse_tree);
+	session_context->query_context = query_context;
+	/* pool_where_to_send(query_context, query_context->original_query, query_context->parse_tree); */
 
 	pool_debug("Close: waiting for master completing the query");
 	if (pool_send_and_wait(query_context, contents, len, 1, MASTER_NODE_ID, "C")
Index: pool_session_context.h
===================================================================
RCS file: /cvsroot/pgpool/pgpool-II/pool_session_context.h,v
retrieving revision 1.19
diff -u -r1.19 pool_session_context.h
--- pool_session_context.h	19 Aug 2010 09:25:40 -0000	1.19
+++ pool_session_context.h	6 Oct 2010 13:40:38 -0000
@@ -61,6 +61,7 @@
 	char *name;		/* portal name */
 	int num_tsparams;
 	PreparedStatement *pstmt;
+	POOL_QUERY_CONTEXT *qctxt;
 } Portal;
 
 /*
Index: pool_session_context.c
===================================================================
RCS file: /cvsroot/pgpool/pgpool-II/pool_session_context.c,v
retrieving revision 1.23
diff -u -r1.23 pool_session_context.c
--- pool_session_context.c	17 Aug 2010 09:23:18 -0000	1.23
+++ pool_session_context.c	6 Oct 2010 13:40:39 -0000
@@ -33,6 +33,8 @@
 
 static void init_prepared_statement_list(void);
 static void init_portal_list(void);
+static bool can_prepared_statement_destroy(POOL_QUERY_CONTEXT *qc);
+static bool can_portal_destroy(POOL_QUERY_CONTEXT *qc);
 
 /*
  * Initialize per session context
@@ -368,6 +370,8 @@
 	{
 		if (strcmp(plist->portals[i]->name, name) == 0)
 		{
+			if (can_portal_destroy(plist->portals[i]->qctxt))
+				pool_query_context_destroy(plist->portals[i]->qctxt);
 			pool_memory_free(session_context->memory_context, plist->portals[i]);
 			break;
 		}
@@ -389,6 +393,7 @@
  * Remove portals by prepared statement name
  * prepared statement : portal = 1 : N
  */
+#ifdef NOT_USED
 static void pool_remove_portal_by_pstmt_name(const char *name)
 {
 	int i;
@@ -413,6 +418,7 @@
 			pool_remove_portal_by_portal_name(plist->portals[i]->name);
 	}
 }
+#endif
 
 /*
  * Remove a prepared statement by prepared statement name
@@ -451,7 +457,8 @@
 	{
 		if (strcmp(pslist->pstmts[i]->name, name) == 0)
 		{
-			pool_query_context_destroy(pslist->pstmts[i]->qctxt);
+			if (can_prepared_statement_destroy(pslist->pstmts[i]->qctxt))
+				pool_query_context_destroy(pslist->pstmts[i]->qctxt);
 			pool_memory_free(session_context->memory_context, pslist->pstmts[i]);
 			break;
 		}
@@ -472,7 +479,11 @@
 	}
 	pslist->size--;
 
-	pool_remove_portal_by_pstmt_name(name);
+	/*
+	 * prepared statements and portals are closed separately
+	 * by a frontend.
+	 */
+	/* pool_remove_portal_by_pstmt_name(name); */
 
 	if (in_progress)
 		pool_set_query_in_progress();
@@ -639,6 +650,7 @@
 	portal->name = pool_memory_strdup(session_context->memory_context, name);
 	portal->num_tsparams = num_tsparams;
 	portal->pstmt = pstmt;
+	portal->qctxt = pstmt->qctxt;
 
 	return portal;
 }
@@ -1137,3 +1149,41 @@
 		exit(1);
 	}
 }
+
+static bool can_prepared_statement_destroy(POOL_QUERY_CONTEXT *qc)
+{
+	int i;
+	PortalList *plist;
+
+	plist = &session_context->portal_list;
+
+	for (i = 0; i < plist->size; i++)
+	{
+		if (plist->portals[i]->qctxt == qc)
+		{
+			pool_debug("can_prepared_statement_destroy: query context is still used.");
+			return false;
+		}
+	}
+
+	return true;
+}
+
+static bool can_portal_destroy(POOL_QUERY_CONTEXT *qc)
+{
+	int i;
+	PreparedStatementList *pslist;
+
+	pslist = &session_context->pstmt_list;
+
+	for (i = 0; i < pslist->size; i++)
+	{
+		if (pslist->pstmts[i]->qctxt == qc)
+		{
+			pool_debug("can_portal_destroy: query context is still used.");
+			return false;
+		}
+	}
+
+	return true;
+}