While working on boonex dolphine 7 you may have seen the error saying:
Error
Database query error
This error is obviously due to some problem with the dolphin 7 (d7) database query that your script / module is generating. So how 
to fix it? first of all if you have recently developed or are developing some module, check out the queries in it to have an idea of what might be going wrong.
Other than that you can simply turn on the debug mode so that the query and error is shown in detail on the page of boonex d7 which has got the error with your database query.
To enable the full debug mode for database in boonex dolphin 7 goto this path:
<site root>/inc/classes/BxDolDb.php
In the above file, look for line number 26 which says:
define( 'DB_FULL_DEBUG_MODE', false );
Change this code to (basically change the false in the end to true):
define( 'DB_FULL_DEBUG_MODE', true );
There you go! your boonex installation is now in full debug mode and you can now check out the errors in detail!