There are two ways to manipulate the data you are connecting and transferring. You can either use a conditional filter which is easy to use or an advanced query statement that requires some knowledge on SQL.
You can select either of these while creating or editing a connection. The filter allows you to only select the data that matches a specific condition. For example, only select all rows where a specific column contains a specific text or number or date.
Query, on the other side, allows you to specify multiple criteria which all begin with the statement SELECT.
We prepared some query examples here.