How to change the area blocksize in datadictionary

Products

• Datacom
• DATACOM - AD
• Datacom/DB

Issue/Introduction

 What modifications are needed in the Datacom datadictionary to change the block size of an area?

Environment

Release: 15.1
Component: Datacom/DB

Resolution

The datadictionary changes can be made directly to the PROD structure.

However if a history of changes is required, then copy the structure to TEST first, modify the blocksize in TEST with the 3002 transaction then copy to PROD and catalog the database. 

The PROD structure can be modified directly using the 1000 ALTER transaction which also updates the CXX without having to close the database.

Sample DDUPDATE cards to make the block size change:

-UPD AREA,area_name(PROD)
1000 ALTER
1500 BLOCK-SIZE,27998

The new blocksize will not take effect until you INIT and re-LOAD the area.

In Datacom 15.1 there is a new Alter Area Block Size (BA24) feature which allows a change to the block size while the data stays available.
 

Additional Information

See Datacom documentation sections 1000 ALTER Transaction and Performing a Block Size Alter 24x7.

See article 244605 Block Size Alter 24x7 BA24 steps and sample JCL