Jdbc

The jdbc command manages the connection pool associated with a JDBC Provider.

The jdbc command uses the following format:

jdbc <providername> clear [-t <timeout>]

or

jdbc <providername> limits [-idle <maxidle>] [-active <maxactive>]

Clear

The clear option closes and removes connections from the connection pool.

• provider name. The name of the JDBC provider toward which the command is directed.
• timeout. The maximum time, in seconds. where the clear command blocks waiting for active connections to be returned to the pool. The default setting is to wait indefinitely.

Notes:

• Execution of this command drops all connections from the pool, but leaves the pool itself intact. Thus, when the next user attempts to borrow a connection from the pool, a new connection will be added to the pool for that user. This means that if a user wants the pool to remain empty for some period of time, channels that use the pool should be stopped before the command runs.
• The pool cannot be cleared completely until all active connections have been returned. If a timeout is not specified, this command will block until all connections have been returned to the pool and closed. If a component borrows a connection from the pool but does not return it-for example, XDSQL Agent using the JDBC provider along with the agent's own connection caching facility-the command would block indefinitely. Avoid this situation by stopping all channels that use the pool before executing this command.
• While the command is actually executing, callers will be unable to borrow connections from the pool. Any attempt will result in an SQL Exception with the message, unable to get pooled connection from this provider. Once all connections have been cleared, however, the pool will become available, as described above.

Limits

The limits option can reset the limits of the pool for the maximum number of idle connections and the maximum number of active connections.

• provider name. The name of the JDBC provider toward which the command is directed.
• idle. New value for maximum number of idle connections to retain in the pool.
• active. New value for maximum number of active connections allowed by the pool.

Notes:

• You must supply at least one of the idle or active options.
• The maximum number of idle connections must always be less than or equal to the maximum number of active connections.
• This command changes only the runtime values of these limits. When restarting iSM, the pool will initialize with the previously saved values.
• This command does not affect connections currently in the pool. After resetting the maximum number of idle connections, the pool can contain more idle connections than the new value, until these connections are borrowed and returned, reach their idle limit and are evicted, or are removed by the clear command.