Implicit connection management for nondefault activation groups

Implicit connection occurs when the application requester detects the first SQL statement issued for the activation group and it is not a CONNECT statement with parameters.

For a distributed program, the implicit connection is made to the relational database specified on the RDB parameter. For a nondistributed program, the implicit connection is made to the local relational database.

Implicit disconnection can occur at the following parts of a process:

• When the activation group ends, if commitment control is not active, activation group level commitment control is active, or the job level commitment definition is at a unit of work boundary.

  If the job level commitment definition is active and not at a unit of work boundary then SQL is placed in the exited state.

• If SQL is in the exited state, when the job level commitment definition is committed or rolled back.
• At the end of a job.

The following example program is not distributed (no connection is required). It is a program run at a Spiffy Corporation regional office to gather local repair information into a report.

CRTSQLxxx PGM(SPIFFY/FIXTOTAL) COMMIT(*CHG) RDB(*NONE)
 
    PROC: FIXTOTAL;
       .
       .
       .
      SELECT * INTO :SERVICE      A
               FROM REPAIRTOT;
    EXEC SQL
    COMMIT;
       .
       .
       .
    END FIXTOTAL;

A

Statement run on the local relational database

Another program, such as the following example, can gather the same information from Spiffy dealerships in the Kansas City region. This is an example of a distributed program that is implicitly connected and disconnected:

CRTSQLxxx PGM(SPIFFY/FIXES) COMMIT(*CHG) RDB(KC101) RDBCNNMTH(*RUW)
 
    PROC: FIXES;
       .
       .
       .
    EXEC SQL
      SELECT * INTO :SERVICE              B
               FROM SPIFFY.REPAIR1;
 
    EXEC SQL  C
     COMMIT;
       .
       .
       .
    END FIXES;  D

B

Implicit connection to application server (AS). The statement runs on the AS.

C

End of unit of work. The application requester (AR) is placed in a connectable and connected state if the COMMIT is successful.

D

Implicit disconnection at the end of the SQL program.