Create Composite Keys

Use the Client Configurator to create composite keys if unique keys haven't been specified in the DMSII data. A composite key is created from a set of column names in a table that's derived from a data set.

If unique keys are not defined and you use Unisys Enterprise Database Server for ClearPath Extended Edition (formerly known as DMSII Extended Edition), the DATABridge Client creates unique keys using RSNs, because they provide the best indexes. If RSNs aren't available, valid AA values are used for keys. This means that if a DMSII reorganization occurs, you will need to reclone all of your data sets. In data sets that don't have fixed length records, the AA values continually change and cannot be used as keys.

Caution: Before you create keys, make sure that your key (the combination of columns) will be unique and will not encounter duplicates. Otherwise, your data can become corrupted. You can only create composite keys for uncloned data sources.

Create a unique composite key

  1. In the Explorer view, right-click a data source and choose Customize Data Source.
  2. In the DMSII view, when you've found the items you want to include in the composite key, select one and set the Item Key to a number. For example, you may assign values of 1, 2, 3, and 4 to four columns to create your composite key. The numbers determine the order of the columns in the index.

    Note: If you can't edit the Item Key value, a key may already be defined for the table. Keys appear in the Relational view with thisKey icon icon.

  3. Select the next item and set the Item Key to the next number in the sequence, and so on until each Item Key is assigned a number.
  4. When you're done, in the menu bar, click Save.