Back-patch fix for errors reported at transaction end.

src/backend/tcop/postgres.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/tcop/postgres.c,v 1.245.2.1 2002/02/26 23:48:45 tgl Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/tcop/postgres.c,v 1.245.2.2 2002/02/27 23:17:01 tgl Exp $
  *
  * NOTES
  *	  this is the "main" module of the postgres backend and
@@ -645,6 +645,15 @@ pg_exec_query_string(char *query_string,		/* string to execute */
 		/* Transaction control statements need some special handling */
 		isTransactionStmt = IsA(parsetree, TransactionStmt);
 
+		/*
+		 * First we set the command-completion tag to the main query
+		 * (as opposed to each of the others that may be generated by
+		 * analyze and rewrite).  Also set ps_status to the main query tag.
+		 */
+		commandTag = CreateCommandTag(parsetree);
+
+		set_ps_display(commandTag);
+
 		/*
 		 * If we are in an aborted transaction, ignore all commands except
 		 * COMMIT/ABORT.  It is important that this test occur before we
@@ -707,18 +716,7 @@ pg_exec_query_string(char *query_string,		/* string to execute */
 
 		/*
 		 * OK to analyze and rewrite this query.
-		 */
-		 
-		/*
-		 * First we set the command-completion tag to the main query
-		 * (as opposed to each of the others that may be generated by
-		 * analyze and rewrite).  Also set ps_status to the main query tag.
-		 */
-		commandTag = CreateCommandTag(parsetree);
-
-		set_ps_display(commandTag);
-
-		/*
+		 *
 		 * Switch to appropriate context for constructing querytrees (again,
 		 * these must outlive the execution context).
 		 */
@@ -858,6 +856,22 @@ pg_exec_query_string(char *query_string,		/* string to execute */
 		}						/* end loop over queries generated from a
 								 * parsetree */
 
+		/*
+		 * If this is the last parsetree of the query string, close down
+		 * transaction statement before reporting command-complete.  This is
+		 * so that any end-of-transaction errors are reported before the
+		 * command-complete message is issued, to avoid confusing clients
+		 * who will expect either a command-complete message or an error,
+		 * not one and then the other.  But for compatibility with
+		 * historical Postgres behavior, we do not force a transaction
+		 * boundary between queries appearing in a single query string.
+		 */
+		if (lnext(parsetree_item) == NIL && xact_started)
+		{
+			finish_xact_command();
+			xact_started = false;
+		}
+
 		/*
 		 * It is possible that the original query was removed due to
 		 * a DO INSTEAD rewrite rule.  In that case we will still have
@@ -877,13 +891,15 @@ pg_exec_query_string(char *query_string,		/* string to execute */
 		 * Tell client that we're done with this query.  Note we emit
 		 * exactly one EndCommand report for each raw parsetree, thus
 		 * one for each SQL command the client sent, regardless of
-		 * rewriting.
+		 * rewriting.  (But a command aborted by error will not send
+		 * an EndCommand report at all.)
 		 */
 		EndCommand(commandTag, dest);
 	}							/* end loop over parsetrees */
 
 	/*
 	 * Close down transaction statement, if one is open.
+	 * (Note that this will only happen if the querystring was empty.)
 	 */
 	if (xact_started)
 		finish_xact_command();
@@ -1688,7 +1704,7 @@ PostgresMain(int argc, char *argv[], const char *username)
 	if (!IsUnderPostmaster)
 	{
 		puts("\nPOSTGRES backend interactive interface ");
-		puts("$Revision: 1.245.2.1 $ $Date: 2002/02/26 23:48:45 $\n");
+		puts("$Revision: 1.245.2.2 $ $Date: 2002/02/27 23:17:01 $\n");
 	}
 
 	/*