Mainframe, MVS and zOS Discussion

Hi,

What happens if we donot set the index before search, will this work?

It depends on what you are trying to do. Have you looked at the documentation, it should be clear what will happen.

Also suggest to try it yourself if you have access to Mainframes.

I came to know that for SEARCH to work in COBOL defining INDEX is mendatory but I could not test it, as I don't have the mainframe access yet.

You could try to install GNU COBOL (formerly OpenCOBOL) to try things out.

It is unclear what you mean exactly by "definiing INDEX is mandatory". SEARCH does no definitions at all.

I wrote a post but i am not able to see it now...

If want the table to be in specific order then the INDEX needs be defined..right?

Ramnath wrote:I wrote a post but i am not able to see it now...

Did you click on the Submit button or just complied a reply? I doubt it was the later case!

There is no necessary relationship between the order of data and whether an INDEX is defined.

If want the table to be in specific order then the INDEX needs be defined..right?

A COBOL table, unlike a VSAM KSDS, does not order the data in the table by the index. Data in a COBOL table is in the order your program loads it. Whether or not an INDEX is defined in the DATA DIVISION has nothing to do with the order of the data.

Hello Ramnath

The thread seems to go nowhere - are you, by chance, talking about SEARCH ALL and the table declaration with INDEX and KEY ASCENDING/DESCENDING?

Yes, I have askedthe same??

Yes, I have askedthe same??

No, you have not. COBOL has the SEARCH verb, which does a sequential search of a table, as well as SEARCH ALL, which does a binary search of a table. The binary SEARCH will fail if the data in the table is not sorted by the index whereas a sequential SEARCH can succeed no matter whether the data is sorted or not. You asked about SEARCH without specifying whether or not you are doing a binary search -- and the SEARCH works very differently compared to SEARCH ALL. If you read the Enterprise COBOL Language Reference manual, you will find that a sequential SEARCH uses an index but that index does not have to be defined on the table you are searching.

I re-read my posts and understand that how less I was making sense in getting the answer. Thanks for your all help, it really heped me to understand about SEARCH and SEARCH ALL.

That's great and thanks for the feedback. Nothing to worry, as you progress in your career you'll learn to explain better yourself.

Thanks Anuj!