Multiple queries can run at the same time, either from multiple tabs within one Query window or from multiple Query windows. Each query is executed in its own thread and has limited impact on other concurrently running queries or on the user interface.
If you run multiple queries from different tabs within the same Query window, SQL Assistant temporarily connects additional sessions using the same connection information you entered for the initial connection. No special context is available to these additional sessions, however, so do not assume that the default database (if you have changed it) or temporary tables are available. If your queries rely on the default database, or on the existence of temporary tables, you should execute/run only one query at a time from within a specific Query window. This ensures that each query uses the same session that was used by the previous query.