Temporary Storage Queues and Transient Data Queues use similar CICS commands to write, read, and delete records in them but their uses are quite different. The following will give you some idea of when to use which.

Temporary Storage Queue

TSQs can be read either sequentially using NEXT or you can specify the number of the record you want to retrieve using ITEM(). Items remain in the TSQ until deleted.

TSQs are either held in virtual storage or in a VSAM file called DFHTEMP.

You can examine the content of a TSQ using the CEBR command. The command can also be used to transfer the content of a TSQ into a TDQ or vice versa.

Transient Data Queue

Records are always retrieved from a TDQ in the same order that they were written. Each record can only be read once as records are automatically deleted when read.

There are two types of TDQ, intrapartition and extrapartition. Intrapartition TDQs are stored in a VSAM file called DFHNTRA. Extrapartition TDQs are stored in QSAM files managed by the operating system and are very inefficient.


This article written by Stephen Chapman, Felgall Pty Ltd.

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