Overview of modifying HALDB databases

Many of the changes that you can make to HALDB databases are the same as those that you can make to other IMS full-function database types. However, some changes are unique to HALDB databases, such as adjusting the distribution of records across the partitions in a HALDB database.

You specify most changes to HALDB databases in either the database definition (DBD) statements that define the HALDB master database or in the DBRC RECON data set where the partition definitions are stored. Where you specify changes depends on the type of change you are making. For example, to change the hierarchical structure of records you specify the changes in the DBD using the DBDGEN process; to modify the range of records stored in a partition you specify the change in the DBRC RECON data set using either the Partition Definition utility or batch DBRC commands.