Meta-queries are queries that provide information about your data (or database) rather than providing the data itself, queries that might display the database version, list available databases, find specific tables or columns, or find non-empty tables. Meta-queries are customized to each predefined database type. So the same meta-query for Oracle (left) will specify different input fields than for SQL Server (right) due to systemic differences.

The figure below shows what is involved in realizing a meta-query (see the user guide for a fuller explanation). The database type of your current connection (1) determines the available set of meta-queries when you open the meta-query selector (2). Choosing a meta-query accesses the query template (3) which generates input fields (4) in the meta-query selector. Your entered values fill the place holders in the query template to produce a completed query (5).