How to Write Read Logic For COBOL Indexed File

In COBOL a file that is defined in Organization is called indexed file. The access mode can be Sequential/Random/Dynamic.


In the below example the first step I have mentioned “Organization is Indexed”.

Select filename-1 Assign to Imp-1
Organization is indexed
Access Mode is Random
Record Key is Part-1

Like any other files you can open indexed files by using INPUT, OUTPUT, IO and EXTEND modes. If you want to read and write into the same file then you need to open as I/O mode.

Tip: Access mode is Random. That means you cannot access the record sequentially.

Read Syntax

Below is the logic to read the indexed file. Here, Part_1 is the key value for the indexed file. The key point is before reading, you need to move Key value.

Move T-partno  to Part-1
Read filename-1
At end Move 'No' to Are-there-no-records
Not at end
     Move T-partno to Part-1
     Read filename-1
       Invalid key  
             Perform 600-err-rtn
       Not Invalid Key   
             Perform 500-ok-rtn
End-Read

Related Posts

Author: Srini

Experienced software developer. Skills in Development, Coding, Testing and Debugging. Good Data analytic skills (Data Warehousing and BI). Also skills in Mainframe.