You can configure a WHERE clause for each table or file in a table pair. If you configure a WHERE clause such that one table in a table pair has signicantly more rows than the other, the OUTER_VALUE and aggregate tests are affected. You can use different WHERE clauses in a table pair to equalize data sets. For example, you can add a WHERE clause on a production environment table has three years of data when the development environment table only has two weeks.

Because the filter condition you enter in the WHERE clause applies to all tests in the table pair, Data Validation Option applies the WHERE clause before it joins the tables. This can improve performance when the WHERE clause filters a large percentage of rows from the source table because the PowerCenter Integration Service processes fewer rows later in the mapping. If you want to enter a condition that filters a small percentage of rows, or you want to apply different filters for different tests, you can enter a filter condition in the Table Pair Test Editor dialog box.

For an XML data source, you can include only child elements of the selected XML group in the WHERE clause.