Activation group connection states

 

A different application server can be established by the explicit or implicit execution of a CONNECT statement.

The following rules apply:

• An activation group cannot have more than one connection to the same application server at the same time.

• When an activation group executes a SET CONNECTION statement, the specified location name must be an existing connection in the set of connections of the activation group.

• When an activation group executes a CONNECT statement, the specified server name must not be an existing connection in the set of connections of the activation group.

If an activation group has a current connection, the activation group is in the connected state.

The CURRENT SERVER special register contains the name of the application server of the current connection. The activation group can execute SQL statements that refer to objects managed by that application server.

An activation group in the unconnected state enters the connected state when it successfully executes a CONNECT or SET CONNECTION statement.

If an activation group does not have a current connection, the activation group is in the unconnected state. The CURRENT SERVER special register contents are equal to blanks. The only SQL statements that can be executed are CONNECT, DISCONNECT, SET CONNECTION, RELEASE, COMMIT, and ROLLBACK.

An activation group in the connected state enters the unconnected state when its current connection is intentionally ended or the execution of an SQL statement is unsuccessful because of a failure that causes a rollback operation at the application server and loss of the connection. Connections are intentionally ended when an activation group successfully executes a commit operation and the connection is in the released state, or when an application process successfully executes the DISCONNECT statement.

 

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