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[Hilltop]

Is there any way to read segments from backwords. First I give a call 'cbltdli' with *L command which read the last record and from there I need to go backward.

Please let me know.

thanks.

[kolusu]

Hiltop,

You can read backwards thru an IMS database if the segment in question has pointers. check this link for Physical Twin Forward and Backward Pointers

Hope this helps...

Cheers

kolusu
_________________
Kolusu
www.linkedin.com/in/kolusu

[Hilltop]

Thanks Kolusu.

So If I put PTR=TB in my segment in the DBD, the successful GN call will take me backward to forward right?

Will try this and let you know.

Thanks.

[Bithead]

You cannot read backwards thru a database - these pointers improve performance when deleting segments as IMS can locate the previous segment using PTB.

[Hilltop]

Thanks Bithead. I guess there is no way to read backward. I remember in ACU cobol reading backward from a file.