RELEASE (Connection)

The RELEASE statement places one or more connections in the release-pending state.

Invocation

This statement can only be embedded within an application program or issued interactively. It is an executable statement that cannot be dynamically prepared. It must not be specified in Java™ or REXX.

Start of change RELEASE is not allowed in a trigger or function. End of change

Authorization

Start of change If a global variable is referenced in a statement, the privileges held by the authorization ID of the statement must include at least one of the following: End of change

For the global variable identified in the statement,
- The READ privilege on the global variable, and
- The system authority *EXECUTE on the library containing the global variable
Administrative authority

Syntax


>>-RELEASE--+-server-name--+-----------------------------------><
            +-variable-----+   
            +-CURRENT------+   
            |      .-SQL-. |   
            '-ALL--+-----+-'

Description

server-name or variable

Identifies a connection by the specified server name or the server name contained in the variable. Start of change

It can be a global variable if it is qualified with schema name. End of change

If a variable is specified:

It must be a character-string variable.
It must not be followed by an indicator variable.
The server name must be left-justified within the variable and must conform to the rules for forming an ordinary identifier.
If the length of the server name is less than the length of the variable, it must be padded on the right with blanks.

When the RELEASE statement is executed, the specified server name or the server name contained in the variable must identify an existing connection of the activation group.

CURRENT

Identifies the current connection of the activation group. The activation group must be in the connected state.

ALL or ALL SQL

Identifies all existing connections of the activation group (local as well as remote connections).

An error or warning does not occur if no connections exist when the statement is executed.

An application server named ALL can only be identified by a variable or a delimited identifier.

If the RELEASE statement is successful, each identified connection is placed in the release-pending state and will therefore be ended during the next commit operation. If the RELEASE statement is unsuccessful, the connection state of the activation group and the states of its connections are unchanged.

Notes

RELEASE and CONNECT (Type 1): Using CONNECT (Type 1) semantics does not prevent using RELEASE.

Scope of RELEASE: RELEASE does not close cursors, does not release any resources, and does not prevent further use of the connection.

Resource considerations for remote connections: Resources are required to create and maintain remote connections. Thus, a remote connection that is not going to be reused should be in the release-pending state and one that is going to be reused should not be in the release-pending state.

Connection states: ROLLBACK does not reset the state of a connection from release-pending to held.

If the current connection is in the release-pending state when a commit operation is performed, the connection is ended and the activation group is in the unconnected state. In this case, the next executed SQL statement must be CONNECT or SET CONNECTION.

RELEASE ALL places the connection to the local release-pending in the release-pending state. A connection in the release-pending state is ended during a commit operation even though it has an open cursor defined with the WITH HOLD clause.

Examples

Example 1: The connection to TOROLAB1 is not needed in the next unit of work. The following statement will cause it to be ended during the next commit operation.

   EXEC SQL RELEASE TOROLAB1;

Example 2: The current connection is not needed in the next unit of work. The following statement will cause it to be ended during the next commit operation.

   EXEC SQL RELEASE CURRENT;

Example 3: None of the existing connections are needed in the next unit of work. The following statement will cause it to be ended during the next commit operation.

   EXEC SQL RELEASE ALL;