Navigate to Configuration > Database Admin and then select the Data Export tab. The second tab 'Custom Export' allows you to create a new custom export. The third tab, 'Saved Exports' lets you run existing custom exports that have been saved.

The essential part of a custom data export is the SQL query that specifies the data to be retrieved from your Kartris database. Defining this requires some technical knowledge and a basic understanding of databases, as well as some knowledge of the Kartris database (although a competent database admin should be able to figure this out). SQL is a standard language, similar versions of which are used on most relational databases from Microsoft's Access and MS SQL to Oracle and MySQL. A tutorial in SQL is beyond the scope of this user guide, but there are many such resources available on the web.

Once you have a query, you can name a custom export, choose the field and string delimiters and then save it with the save button on the toolbar. You can also run exports directly from here with the export button on the toolbar.