Sometimes it is necessary to only export some of the submissions that have been uploaded. In this case you can use the Filter field on the Format tab. The filter expression can use placeholder values for submission data.
If any filter expression is entered, it must evaluate to true for the record to be exported. If no filter expression is entered then all records received will be exported.
See here for more details on writing filter expressions.
The filter expression is evaluated for each record that would be exported. If you have a repeating section in your submission, the filter expression will be evaluated for each detail record that would be exported.
The filter does not affect which submissions are downloaded or removed from the server, just which records are exported.