CAF connection functions

A CAF connection function specifies the action that you want CAF to take. You specify these functions when you invoke CAF through CALL DSNALI statements.

You can specify the following CAF functions in a CALL DSNALI statement:

CONNECT: Establishes the task (TCB) as a user of the named DB2® subsystem. When the first task within an address space issues a connection request, the address space is also initialized as a user of DB2.
OPEN: Allocates a DB2 plan. You must allocate a plan before DB2 can process SQL statements. If you did not request the CONNECT function, the OPEN function implicitly establishes the task, and optionally the address space, as a user of DB2.
CLOSE: Commits or abnormally terminates any database changes and deallocates the plan. If the OPEN function implicitly requests the CONNECT function, the CLOSE function removes the task, and possibly the address space, as a user of DB2.
DISCONNECT: Removes the task as a user of DB2 and, if this task is the last or only task in the address space with a DB2 connection, terminates the address space connection to DB2.
TRANSLATE: Returns an SQL code and printable text that describe a DB2 hexadecimal error reason code. This information is returned to the SQLCA.
Restriction: You cannot call the TRANSLATE function from the Fortran language.

Recommendation: Because the effect of any CAF function depends on what functions the program has already run, carefully plan the calls that your program makes to these CAF connection functions. Read about the summary of CAF behavior and make these function calls accordingly.

CONNECT function for CAF
The CAF CONNECT function initializes a connection to DB2. This function is different than the SQL CONNECT statement that accesses a remote location within DB2.
OPEN function for CAF
The OPEN function allocates DB2 resources that are needed to run the specified plan or to issue IFI requests. If the requesting task does not already have a connection to the named DB2 subsystem, the OPEN function establishes it.
CLOSE function for CAF
The CAF CLOSE function deallocates the plan that was created either explicitly by a call to the OPEN function or implicitly at the first SQL call. Optionally, the CLOSE function also disconnects the task, and possibly the address space, from DB2.
DISCONNECT function for CAF
The CAF DISCONNECT function terminates a connection to DB2.
TRANSLATE function for CAF
The TRANSLATE function converts a DB2 hexadecimal error reason code from a failed OPEN request into an SQL error code and printable error message text. DB2 places the information into the SQLCODE and SQLSTATE host variables or related fields of the SQLCA of the caller.

Parent topic: Invoking the call attachment facility

Related concepts:

Summary of CAF behavior

CALL DSNALI statement parameter list