[SQL] encryption/decryption

hi all, just to ask u all one thing regarding encryption/decryption. i am migrating my database from mysql to pgSQL using a php script. in mysql there is a table 'users' where a field 'password' is there of type varchar(30), and is encrypted using AES algorithm, and when i check all the records in

[SQL] cross tables, SELECT expressions, and GROUP BY problem

Hi, I'm relatively stretched when it comes to SQL but I'm getting there. I have a question though: Thanks to various web sites I've succeeded in creating simple cross tables in PostgreSQL. I'm now trying more complicated examples (migrating queries from MS Access to PostgreSQL). I'm stuck on gett