From 00d4f2af8bd6a1b9db2f676cc76b64d98ace99fb Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Mon, 3 Feb 2014 21:30:02 -0500 Subject: Improve connection-failure error handling in contrib/postgres_fdw. postgres_fdw tended to say "unknown error" if it tried to execute a command on an already-dead connection, because some paths in libpq just return a null PGresult for such cases. Out-of-memory might result in that, too. To fix, pass the PGconn to pgfdw_report_error, and look at its PQerrorMessage() string if we can't get anything out of the PGresult. Also, fix the transaction-exit logic to reliably drop a dead connection. It was attempting to do that already, but it assumed that only connection cache entries with xact_depth > 0 needed to be examined. The folly in that is that if we fail while issuing START TRANSACTION, we'll not have bumped xact_depth. (At least for the case I was testing, this fix masks the other problem; but it still seems like a good idea to have the PGconn fallback logic.) Per investigation of bug #9087 from Craig Lucas. Backpatch to 9.3 where this code was introduced. --- contrib/postgres_fdw/postgres_fdw.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'contrib/postgres_fdw/postgres_fdw.h') diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h index 85fc25aaef4..228345d7864 100644 --- a/contrib/postgres_fdw/postgres_fdw.h +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -30,8 +30,8 @@ extern PGconn *GetConnection(ForeignServer *server, UserMapping *user, extern void ReleaseConnection(PGconn *conn); extern unsigned int GetCursorNumber(PGconn *conn); extern unsigned int GetPrepStmtNumber(PGconn *conn); -extern void pgfdw_report_error(int elevel, PGresult *res, bool clear, - const char *sql); +extern void pgfdw_report_error(int elevel, PGresult *res, PGconn *conn, + bool clear, const char *sql); /* in option.c */ extern int ExtractConnectionOptions(List *defelems, -- cgit v1.2.3