Is it possible a trigger on a select statement with MySQL?

I know that triggers can be used on insert, update and delete, but what about a trigger (or sort of) on a select statement. I want to use a 开发者_如何学JAVAtrigger to insert data on a table B when it is selected an existent record on a table A, it could be possible?.

Thanks in advance.

You should design your application so that database access occurs only through certain methods, and in those methods, add the monitoring you need.

Not exactly a trigger, but you can:

CREATE FUNCTION myFunc(...) BEGIN INSERT INTO myTable VALUES(...) END;

And then

SELECT myFunc(...), ... FROM otherTable WHERE id = 1;

Not an elegant solution, though.

It is not possible in the database itself.

However there are monitoring/instrumentation products for databases (e.g. for Sybase - not sure about MySQL) which track every query executed by the server, and can do anything based on that - usually store the query log into a data warehouse for later analysis, but they can just as well insert a record into table B for you, I would guess.

You can write an application which will be monitoring the query log and doing something when a select occurs. A pretty crude way to solve the problem though...