The SQL Queries tab on the Database Explorer looks like this:
This tab is only for very experienced database users. With it, you can perform any SQL query or operation on your database (and remember, there is no "undo" feature). In the above example, a SQL select query was typed that listed a subset of the records in the Stations table.
There are many sources of information on writing SQL queries and commands. Please be aware that each provider has a slightly different syntax for performing queries. A good comparison of several popular providers can be found at www.sqlzoo.net
Please use this feature with caution as it is not difficult to make modifications to tables that will break WRDB (imagine removing the Station_ID column from your data table!).