You can define a column in a source definition as a key field. When you define a column as a key field, you ensure that the PowerCenter Integration Service does not transfer documents that contain a null value for this column.

Consider an example where you want to extract data from a Notes database and load it into a relational database. The target tables can contain primary-key or foreign-key columns that cannot contain null values.

Define the column in the source definition as a key field. The PowerCenter Integration Service filters documents that contain null values for this column.