PSQL Auto-Reconnect
PSQL Auto-Reconnect (PARC) allows client-server or workgroup applications to endure temporary network interruptions without canceling the current database operation. When PSQL detects a network interruption, it automatically attempts to reconnect at specific intervals for a configurable amount of time. This feature also preserves the client context so that when communications are re-established, database access continues exactly where it left off when the network interruption occurred.
This feature preserves the application context and attempts to reconnect regardless of whether the client or server was attempting to send data at the moment when the network communications were interrupted.
When a network interruption occurs, the reconnect attempts occur at specific intervals. For all connections, successive attempts are made at 0.5, 1, 2, 4, and 8 seconds, continuing every 8 seconds thereafter until the AutoReconnect Timeout value is reached. If no attempt is successful before the maximum wait time is reached, then the current operation fails and the client connection is reset. The maximum wait time is configurable between 45 seconds and 65,535 seconds.
This feature is disabled by default. For this feature to operate, you must select
Enable Auto Reconnect (Windows only)
for both client and server configurations. You can specify the time-out value using the server setting
Auto Reconnect Timeout
.
Remarks
This feature is supported for Btrieve, ODBC, and DTI connections.
The Btrieve communication servers may write out *.PAR or *.SAR files to the Transaction Log Directory. These are temporary files that contain the context for the last item that the server tried to send to the client. When a reconnection occurs, the client may ask for data to be re-sent. The server reads these files to obtain the appropriate data. These files are normally deleted by the server after the data is read or later when the connection is finally terminated.