A trigger for queries

I`ve got a problem I can´t solve. What I want is to handle all the queries (SELECT) before ORACLE prccesses them. The purpose is to control the access to data but in a "smart" way (that´s, with really complex rules). So I´ve dessign a program that analyzes the code of the SELECT SQL sentence and checks if the user has access to the data requested. I´d thought to run it just before would proccess the sentence.

I´ve tried with TRIGGERS but, unfortunately, i´ve could see they only work with INSERT, DELETE and UPDATE sentences, not with SELECT.

i really have no idea what to do. If anyone can help me I´ll thank very much. Received on Sat Feb 07 1998 - 00:00:00 CST