Mainframe Interview Questions

Supply the DD cards just as you would for files referred to in the main program.

To insert a NULL, move -1 to the null indicator

To insert a valid value, move 0 to the null indicator

- Use a COBOL II CALL statement to invoke a subprogram. This method is transparent to CICS, which sees only the one load module. 

- EXEC LINK is similar to a call; it invokes a separate CICS program and ends with a RETURN to the invoking program

- EXEC XCTL which transfers control to another CICS program and does not get control 

back. 

COBOL II allows for static calls which are more efficient than the LINK instruction which establishes a new run-unit. 

An application plan or package is generated by the bind to define an access path. 

1. Based on the lock-size given while creating the table space

2. Programer can direct the DB2 what lock-size to use

3. If lock - size ANY is specified, DB2 usually chooses a lock-size of PAGE

IDENTIFICATION DIVISION and PROGRAM-ID paragraph are mandatory for a compilation error free COBOL program.

There are some differences:

COBOL II supports structured programming by using in line Performs and explicit scope terminators. It introduces new features (EVALUATE, SET. TO TRUE, CALL BY CONTEXT, etc). It permits programs to be loaded and addressed above the 16-megabyte line .  It does not support many old features (READY TRACE, REPORT-WRITER, ISAM, etc.). It offers enhanced CICS support.

An OOK-Rec is a one of a kind record set, used to get to another record set.