Fix the following bugs in master_slave mode && load_balance mode.

We force to replicate PREPARE and DEALLOCATE statement because of the case.

  PREPARE xx AS SELECT 1;
  EXECUTE xx;

If EXECUTE statement was load balanced, it occured the error.

  ERROR:  prepared statement "xx" does not exist

diff --git a/pool_process_query.c b/pool_process_query.c
index e7b26f609c16f85bd31caad390ea3cc7fe63679e..f3750a71db892a0ef911600a85c74aec5186b527 100644 (file)
--- a/pool_process_query.c
+++ b/pool_process_query.c
@@ -156,6 +156,9 @@ static PreparedStatement *pending_prepared_stmt = NULL;
 static PreparedStatementList prepared_list; /* prepared statement name list */
 static PreparedStatement *unnamed_statement = NULL;
 static PreparedStatement *unnamed_portal = NULL;
+static int force_replication = 0; /* non 0 if force to replicate query */
+static int prepare_in_session = 0;
+
 static int is_drop_database(char *query);              /* returns non 0 if this is a DROP DATABASE command */
 static void query_ps_status(char *query, POOL_CONNECTION_POOL *backend);               /* show ps status */
 static int detect_deadlock_error(POOL_CONNECTION *master, int major);
@@ -218,6 +221,7 @@ POOL_STATUS pool_process_query(POOL_CONNECTION *frontend,
                        else    /* no more query(st == 2) */
                        {
                                frontend->no_forward = 0;
+                               prepare_in_session = 0;
                                return POOL_CONTINUE;
                        }
 
@@ -611,6 +615,8 @@ static POOL_STATUS Query(POOL_CONNECTION *frontend,
                {
                        pending_function = add_prepared_list;
                        pending_prepared_stmt = stmt;
+                       force_replication = 1;
+                       prepare_in_session = 1;
                }
        }
        else if (frontend &&
@@ -647,6 +653,7 @@ static POOL_STATUS Query(POOL_CONNECTION *frontend,
                        return POOL_END;
                }
                free(buf);
+               force_replication = 1;
        }
 
        if (frontend &&
@@ -675,9 +682,18 @@ static POOL_STATUS Query(POOL_CONNECTION *frontend,
                string1 = string;
        }
 
+       /* reset query have to be replicated */
+       if (frontend == NULL && prepare_in_session)
+               force_replication = 1;
+
        /* load balance trick */
        if (load_balance_enabled(backend, string1))
                start_load_balance(backend);
+       else if (force_replication)
+       {
+               replication_was_enabled = REPLICATION;
+               REPLICATION = 1;
+       }
        else if (MASTER_SLAVE)
        {
                master_slave_was_enabled = 1;
@@ -1084,6 +1100,13 @@ static POOL_STATUS ReadyForQuery(POOL_CONNECTION *frontend,
                master_slave_dml = 0;
        }
 
+       if (force_replication)
+       {
+               force_replication = 0;
+               REPLICATION = replication_was_enabled;
+               replication_was_enabled = 0;
+       }
+
 #ifdef NOT_USED
        return ProcessFrontendResponse(frontend, backend);
 #endif
@@ -1958,7 +1981,6 @@ static POOL_STATUS ProcessFrontendResponse(POOL_CONNECTION *frontend,
                                        MASTER_SLAVE = 0;
                                        master_slave_dml = 1;
                                }
-
                                status = SimpleForwardToBackend(fkind, frontend, backend);
                                if (pool_flush(MASTER(backend)))
                                        status = POOL_ERROR;
@@ -3538,6 +3560,12 @@ static PreparedStatement *get_prepared_command_portal_and_statement(char *query)
        /* skip data type list */
        while (*query && *query != ')')
                query++;
+
+       if (!*query)
+       {
+               pool_debug("get_prepared_command_portal_and_statement: could not get statement");
+               return NULL;
+       }
        query++;
 
        /* skip spaces */