Re: Enforce business rule with before insert trigger?

[Andrew Gilfrin]

I came across the same problem when writing content for my web site. I was writting a section on how you could use triggers to emulate check constraints in a similar way to you.

However I hit a wall when trying to find a solution to this problem. The only way I could see to do this is artificially raise an error for example by accessing a table that doesn't exist, but as you can't compile a trigger with SQL I was finding it difficult to find an alternative.

Anyway this method is really not very good because the error message raised would not be consistent with the problem.

In the end I gave up as it seemed to be too much messing around for an inferior solution.

I think the crux for you post is this line "also making sure I'm passing some sort of coherent message back to the user" thats the real problem and thats why I decided any solution would not be suitable.

Andrew Gilfrin
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