The Database Explorer window displays all your objects, grouped by Schema name.
With DB2, when you configure an ODBC Datasource, you can specify a setting (SCHEMALIST) that will restrict the list of schemas to those specified.
This setting is used by the inbuilt ODBC functions (eg. SQLTables) that display the schemas and tables. AQT does not use these ODBC functions, instead uses its own queries. As a result, AQT is not aware of and ignores the SCHEMALIST setting.
However it is possible to configure AQT to use the SCHEMALIST setting. To do this: