Sample DMSII Reorganization

This section illustrates an example of DMSII reorganizations involving year 2000 conversions.

In this example, a DMSII item of type NUMBER(6) holds a date value of the form mmddyy (dms_subtype of 13) in the data set ORDERS. The DATABridge Client uses user scripts to map this value as a relational database date type (that is, Oracle date or Microsoft SQL Server smalldatetime).

First DMSII Reorganization

The first DMSII reorganization involving year 2000 conversions would be similar to the following:

  • Perform a reorganization to add a new item of type NUMBER(8) to the ORDERS data set. This new item holds a year 2000 date of the form mmddyyyy.
  • Populate the new column with the expanded date values. As you migrate applications to use the new column, eventually you can drop the old column by doing another reorganization.

It is not necessary to reclone the ORDERS data set because the DATABridge Client can handle the expansion of the year to a four-digit value.

Second DMSII Reorganization

The second reorganization is much easier as it involves dropping the old item of NUMBER(6). The redefine command detects that the relational database table schema is not affected by the reorganization since the dropped item is not being cloned.

The only additional step is to remove the update statement (in script.user_layout.orders) for the old order_date item that no longer exists. Failure to do this would not be fatal as the SQL engine finds no rows to update, which would not be returned as an error.