Situations that Do and Do Not Need a Rules File

You need a rules file if the data source does not map perfectly to the database or if you are performing any of the following tasks:

You do not need a rules file if you are performing a data load and the data source maps perfectly to the database. See Data Sources that Do Not Need a Rules File.

Note:

If you are using a rules file, the number of fields in each record in the rules file must match. See Dealing with Missing Fields in a Data Source.