Let me get this straight: you have no problems using a single SQLite database connection, but you can not make a second one work?

You can call addDatabase() twice; just be sure to give different connection names in the two calls. In subsequent calls to QSqlDatabase::database() put the name of the desired connection to the argument list.

For your errors: Show us some code please, we cannot guess what you are doing.

Hi, All: Thanks a lot. I just follow your recommendation, and it works now.