The stack trace might not display all you want, however, try peeking at tab on the right: might be the select statements (probably the very last one) are causing the error, you might wanna check them out.
Also, I would recommend use appropriate types for your tables in your SQL database, such an error indicates an error in the architecture, you might want to reconsider (or at least, check out each row for its type) your database types for the data the might carry.