web designer - database query


I'm trying to create a database query because I need some data from more database table so I would like to use join.

First I've tried with adding it manually to the collections. The sql expression is the simplest for just the sake of test - like 'select UID_TroubleTicket from TroubleTicket where isClosed = 0''. I tried it with adding the UID_TroubleTicket property to the collection also. Unfortunately the collection is always empty. Tried it with loading the data in the Initializer, but with that I got an error.

I've tried it with the wizard, it showed me the data in the window where I can test my query, but than when I open the page it shows error:

One or more errors occurred.
One or more errors occurred.
One or more errors occurred.
The SQL result set has no common properties with the collection.
My version is 7.1.4.
Any example how can I use it would be amazing...