Is there a way to change the exception message in oracle?

I have 开发者_开发知识库a PHP application on top of an Oracle DB. In the database, there are some constraints defined. When they get violated, I get a plain constraint violated message. I would like to have some custom message shown to the user.

Is there a way to define in the definition of the constraint a custom error message ? Or how would you suggest me to approach this issue ?

Thanks!

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Catch the exception and inform the user however you feel is appropriate.

php: catch exception and continue execution, is it possible?

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Ask yourself why your invalid data is reaching your database?

You should implement strong validation on your inputs to prevent this happening as the constraints are only there as a last resort, not a front line for validating data.

Create validation routines that trap and report back (with a useful message) invalid data only sending valid data to be inserted into your database.

This could be done using PL/SQL stored procedures/packages/functions, a good article on using them for CRUD operations is here: http://www.devshed.com/c/a/Oracle/Developing-Simple-PL-SQL-Stored-Procedures-for-CRUD-Operations/

Or you could potentially use database triggers for this purpose, though "BEFORE" operation triggers are not as efficient as bulk processing collection data in a PL/SQL validation package.

Hope this helps...