Mainframe Interview Questions

Go to file-aid copy option.Enter the from dataset to be copied and to dataset to which you want to copy.go to options. Enter 0 at Initial records to skip field.Then enter 3 at the no of records to skip field and 1 to no of records to select.press enter and PF3.

- A status occurs when image copy on a table needs to be taken

- The table is available only for queries and can not be updated

- COPY PENDING status can be removed by taking away the image copy or by using REPAIR utility

The number of distinct values for a column is called index cardinality. DB2's RUNSTATS utility analyzes column value redundancy to determine whether to use a tablespace or index scan to search for data.

USING HOST VARIABLE we can pass data from COBOL to DB2

Following guidelines to be following while writing Cobol program:

- Use ? EVALUATE ? statement for constructing cases.

- Use scope terminators for nesting.

- Use in-line Perform statement for writing ?do? constructions.

- Use Test Before and Test After in the Perform statement while writing Do-While statements.

A31. The self-referencing constraint limits in a single table the changes to a primary key that the related foreign key defines. The foreign key in a self referencing table must specify the DELETE CASCADE rule.

The enter and PF keys transmit data from the screen; the PA keys tell CICS that a terminal action took place, but data is not transmitted.

The LOAD command retrieves an object program from disk and loads it into main storage - it's primarily used for a constant table that will be available system-wide.