diff --git a/contrib/postgres_fdw/connection.c b/contrib/postgres_fdw/connection.c
index 93ea498012609c1fdba918f3a29d964b14e0baf5..b688241283805d7d0c57375c90ccd610967def5e 100644
--- a/contrib/postgres_fdw/connection.c
+++ b/contrib/postgres_fdw/connection.c
@@ -355,7 +355,7 @@ do_sql_command(PGconn *conn, const char *sql)
res = PQexec(conn, sql);
if (PQresultStatus(res) != PGRES_COMMAND_OK)
- pgfdw_report_error(ERROR, res, true, sql);
+ pgfdw_report_error(ERROR, res, conn, true, sql);
PQclear(res);
}
@@ -454,6 +454,7 @@ GetPrepStmtNumber(PGconn *conn)
*
* elevel: error level to use (typically ERROR, but might be less)
* res: PGresult containing the error
+ * conn: connection we did the query on
* clear: if true, PQclear the result (otherwise caller will handle it)
* sql: NULL, or text of remote command we tried to execute
*
@@ -462,7 +463,8 @@ GetPrepStmtNumber(PGconn *conn)
* marked with have_error = true.
*/
void
-pgfdw_report_error(int elevel, PGresult *res, bool clear, const char *sql)
+pgfdw_report_error(int elevel, PGresult *res, PGconn *conn,
+ bool clear, const char *sql)
{
/* If requested, PGresult must be released before leaving this function. */
PG_TRY();
@@ -483,6 +485,14 @@ pgfdw_report_error(int elevel, PGresult *res, bool clear, const char *sql)
else
sqlstate = ERRCODE_CONNECTION_FAILURE;
+ /*
+ * If we don't get a message from the PGresult, try the PGconn. This
+ * is needed because for connection-level failures, PQexec may just
+ * return NULL, not a PGresult at all.
+ */
+ if (message_primary == NULL)
+ message_primary = PQerrorMessage(conn);
+
ereport(elevel,
(errcode(sqlstate),
message_primary ? errmsg_internal("%s", message_primary) :
@@ -525,74 +535,37 @@ pgfdw_xact_callback(XactEvent event, void *arg)
{
PGresult *res;
- /* We only care about connections with open remote transactions */
- if (entry->conn == NULL || entry->xact_depth == 0)
+ /* Ignore cache entry if no open connection right now */
+ if (entry->conn == NULL)
continue;
- elog(DEBUG3, "closing remote transaction on connection %p",
- entry->conn);
-
- switch (event)
+ /* If it has an open remote transaction, try to close it */
+ if (entry->xact_depth > 0)
{
- case XACT_EVENT_PRE_COMMIT:
- /* Commit all remote transactions during pre-commit */
- do_sql_command(entry->conn, "COMMIT TRANSACTION");
-
- /*
- * If there were any errors in subtransactions, and we made
- * prepared statements, do a DEALLOCATE ALL to make sure we
- * get rid of all prepared statements. This is annoying and
- * not terribly bulletproof, but it's probably not worth
- * trying harder.
- *
- * DEALLOCATE ALL only exists in 8.3 and later, so this
- * constrains how old a server postgres_fdw can communicate
- * with. We intentionally ignore errors in the DEALLOCATE, so
- * that we can hobble along to some extent with older servers
- * (leaking prepared statements as we go; but we don't really
- * support update operations pre-8.3 anyway).
- */
- if (entry->have_prep_stmt && entry->have_error)
- {
- res = PQexec(entry->conn, "DEALLOCATE ALL");
- PQclear(res);
- }
- entry->have_prep_stmt = false;
- entry->have_error = false;
- break;
- case XACT_EVENT_PRE_PREPARE:
-
- /*
- * We disallow remote transactions that modified anything,
- * since it's not really reasonable to hold them open until
- * the prepared transaction is committed. For the moment,
- * throw error unconditionally; later we might allow read-only
- * cases. Note that the error will cause us to come right
- * back here with event == XACT_EVENT_ABORT, so we'll clean up
- * the connection state at that point.
- */
- ereport(ERROR,
- (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
- errmsg("cannot prepare a transaction that modified remote tables")));
- break;
- case XACT_EVENT_COMMIT:
- case XACT_EVENT_PREPARE:
- /* Should not get here -- pre-commit should have handled it */
- elog(ERROR, "missed cleaning up connection during pre-commit");
- break;
- case XACT_EVENT_ABORT:
- /* Assume we might have lost track of prepared statements */
- entry->have_error = true;
- /* If we're aborting, abort all remote transactions too */
- res = PQexec(entry->conn, "ABORT TRANSACTION");
- /* Note: can't throw ERROR, it would be infinite loop */
- if (PQresultStatus(res) != PGRES_COMMAND_OK)
- pgfdw_report_error(WARNING, res, true,
- "ABORT TRANSACTION");
- else
- {
- PQclear(res);
- /* As above, make sure we've cleared any prepared stmts */
+ elog(DEBUG3, "closing remote transaction on connection %p",
+ entry->conn);
+
+ switch (event)
+ {
+ case XACT_EVENT_PRE_COMMIT:
+ /* Commit all remote transactions during pre-commit */
+ do_sql_command(entry->conn, "COMMIT TRANSACTION");
+
+ /*
+ * If there were any errors in subtransactions, and we
+ * made prepared statements, do a DEALLOCATE ALL to make
+ * sure we get rid of all prepared statements. This is
+ * annoying and not terribly bulletproof, but it's
+ * probably not worth trying harder.
+ *
+ * DEALLOCATE ALL only exists in 8.3 and later, so this
+ * constrains how old a server postgres_fdw can
+ * communicate with. We intentionally ignore errors in
+ * the DEALLOCATE, so that we can hobble along to some
+ * extent with older servers (leaking prepared statements
+ * as we go; but we don't really support update operations
+ * pre-8.3 anyway).
+ */
if (entry->have_prep_stmt && entry->have_error)
{
res = PQexec(entry->conn, "DEALLOCATE ALL");
@@ -600,8 +573,50 @@ pgfdw_xact_callback(XactEvent event, void *arg)
}
entry->have_prep_stmt = false;
entry->have_error = false;
- }
- break;
+ break;
+ case XACT_EVENT_PRE_PREPARE:
+
+ /*
+ * We disallow remote transactions that modified anything,
+ * since it's not very reasonable to hold them open until
+ * the prepared transaction is committed. For the moment,
+ * throw error unconditionally; later we might allow
+ * read-only cases. Note that the error will cause us to
+ * come right back here with event == XACT_EVENT_ABORT, so
+ * we'll clean up the connection state at that point.
+ */
+ ereport(ERROR,
+ (errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
+ errmsg("cannot prepare a transaction that modified remote tables")));
+ break;
+ case XACT_EVENT_COMMIT:
+ case XACT_EVENT_PREPARE:
+ /* Pre-commit should have closed the open transaction */
+ elog(ERROR, "missed cleaning up connection during pre-commit");
+ break;
+ case XACT_EVENT_ABORT:
+ /* Assume we might have lost track of prepared statements */
+ entry->have_error = true;
+ /* If we're aborting, abort all remote transactions too */
+ res = PQexec(entry->conn, "ABORT TRANSACTION");
+ /* Note: can't throw ERROR, it would be infinite loop */
+ if (PQresultStatus(res) != PGRES_COMMAND_OK)
+ pgfdw_report_error(WARNING, res, entry->conn, true,
+ "ABORT TRANSACTION");
+ else
+ {
+ PQclear(res);
+ /* As above, make sure to clear any prepared stmts */
+ if (entry->have_prep_stmt && entry->have_error)
+ {
+ res = PQexec(entry->conn, "DEALLOCATE ALL");
+ PQclear(res);
+ }
+ entry->have_prep_stmt = false;
+ entry->have_error = false;
+ }
+ break;
+ }
}
/* Reset state to show we're out of a transaction */
@@ -689,7 +704,7 @@ pgfdw_subxact_callback(SubXactEvent event, SubTransactionId mySubid,
curlevel, curlevel);
res = PQexec(entry->conn, sql);
if (PQresultStatus(res) != PGRES_COMMAND_OK)
- pgfdw_report_error(WARNING, res, true, sql);
+ pgfdw_report_error(WARNING, res, entry->conn, true, sql);
else
PQclear(res);
}
diff --git a/contrib/postgres_fdw/postgres_fdw.c b/contrib/postgres_fdw/postgres_fdw.c
index ae3ab000e1f34a4a665676d869713b7f396d5dcf..fde1ec13617d80ead676860a57a07b7c648575a4 100644
--- a/contrib/postgres_fdw/postgres_fdw.c
+++ b/contrib/postgres_fdw/postgres_fdw.c
@@ -1040,7 +1040,7 @@ postgresReScanForeignScan(ForeignScanState *node)
*/
res = PQexec(fsstate->conn, sql);
if (PQresultStatus(res) != PGRES_COMMAND_OK)
- pgfdw_report_error(ERROR, res, true, sql);
+ pgfdw_report_error(ERROR, res, fsstate->conn, true, sql);
PQclear(res);
/* Now force a fresh FETCH. */
@@ -1374,7 +1374,7 @@ postgresExecForeignInsert(EState *estate,
0);
if (PQresultStatus(res) !=
(fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK))
- pgfdw_report_error(ERROR, res, true, fmstate->query);
+ pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query);
/* Check number of rows affected, and fetch RETURNING tuple if any */
if (fmstate->has_returning)
@@ -1444,7 +1444,7 @@ postgresExecForeignUpdate(EState *estate,
0);
if (PQresultStatus(res) !=
(fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK))
- pgfdw_report_error(ERROR, res, true, fmstate->query);
+ pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query);
/* Check number of rows affected, and fetch RETURNING tuple if any */
if (fmstate->has_returning)
@@ -1514,7 +1514,7 @@ postgresExecForeignDelete(EState *estate,
0);
if (PQresultStatus(res) !=
(fmstate->has_returning ? PGRES_TUPLES_OK : PGRES_COMMAND_OK))
- pgfdw_report_error(ERROR, res, true, fmstate->query);
+ pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query);
/* Check number of rows affected, and fetch RETURNING tuple if any */
if (fmstate->has_returning)
@@ -1563,7 +1563,7 @@ postgresEndForeignModify(EState *estate,
*/
res = PQexec(fmstate->conn, sql);
if (PQresultStatus(res) != PGRES_COMMAND_OK)
- pgfdw_report_error(ERROR, res, true, sql);
+ pgfdw_report_error(ERROR, res, fmstate->conn, true, sql);
PQclear(res);
fmstate->p_name = NULL;
}
@@ -1800,7 +1800,7 @@ get_remote_estimate(const char *sql, PGconn *conn,
*/
res = PQexec(conn, sql);
if (PQresultStatus(res) != PGRES_TUPLES_OK)
- pgfdw_report_error(ERROR, res, false, sql);
+ pgfdw_report_error(ERROR, res, conn, false, sql);
/*
* Extract cost numbers for topmost plan node. Note we search for a
@@ -1934,7 +1934,7 @@ create_cursor(ForeignScanState *node)
res = PQexecParams(conn, buf.data, numParams, NULL, values,
NULL, NULL, 0);
if (PQresultStatus(res) != PGRES_COMMAND_OK)
- pgfdw_report_error(ERROR, res, true, fsstate->query);
+ pgfdw_report_error(ERROR, res, conn, true, fsstate->query);
PQclear(res);
/* Mark the cursor as created, and show no tuples have been retrieved */
@@ -1985,7 +1985,7 @@ fetch_more_data(ForeignScanState *node)
res = PQexec(conn, sql);
/* On error, report the original query, not the FETCH. */
if (PQresultStatus(res) != PGRES_TUPLES_OK)
- pgfdw_report_error(ERROR, res, false, fsstate->query);
+ pgfdw_report_error(ERROR, res, conn, false, fsstate->query);
/* Convert the data into HeapTuples */
numrows = PQntuples(res);
@@ -2091,7 +2091,7 @@ close_cursor(PGconn *conn, unsigned int cursor_number)
*/
res = PQexec(conn, sql);
if (PQresultStatus(res) != PGRES_COMMAND_OK)
- pgfdw_report_error(ERROR, res, true, sql);
+ pgfdw_report_error(ERROR, res, conn, true, sql);
PQclear(res);
}
@@ -2128,7 +2128,7 @@ prepare_foreign_modify(PgFdwModifyState *fmstate)
NULL);
if (PQresultStatus(res) != PGRES_COMMAND_OK)
- pgfdw_report_error(ERROR, res, true, fmstate->query);
+ pgfdw_report_error(ERROR, res, fmstate->conn, true, fmstate->query);
PQclear(res);
/* This action shows that the prepare has been done. */
@@ -2278,7 +2278,7 @@ postgresAnalyzeForeignTable(Relation relation,
{
res = PQexec(conn, sql.data);
if (PQresultStatus(res) != PGRES_TUPLES_OK)
- pgfdw_report_error(ERROR, res, false, sql.data);
+ pgfdw_report_error(ERROR, res, conn, false, sql.data);
if (PQntuples(res) != 1 || PQnfields(res) != 1)
elog(ERROR, "unexpected result from deparseAnalyzeSizeSql query");
@@ -2372,7 +2372,7 @@ postgresAcquireSampleRowsFunc(Relation relation, int elevel,
{
res = PQexec(conn, sql.data);
if (PQresultStatus(res) != PGRES_COMMAND_OK)
- pgfdw_report_error(ERROR, res, false, sql.data);
+ pgfdw_report_error(ERROR, res, conn, false, sql.data);
PQclear(res);
res = NULL;
@@ -2403,7 +2403,7 @@ postgresAcquireSampleRowsFunc(Relation relation, int elevel,
res = PQexec(conn, fetch_sql);
/* On error, report the original query, not the FETCH. */
if (PQresultStatus(res) != PGRES_TUPLES_OK)
- pgfdw_report_error(ERROR, res, false, sql.data);
+ pgfdw_report_error(ERROR, res, conn, false, sql.data);
/* Process whatever we got. */
numrows = PQntuples(res);
diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h
index 85fc25aaef4a1bcd0050bd1e679efb1abc2d46ee..228345d78644df7972d95e5d4129e4920d6e6874 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,