COBOL Indexed File how to read logic

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 data-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

In the below example, I am reading an indexed file. The speciality is before reading I am just  moving key value.

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

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