Trigger Or Constraint?

Andy Levy points out that you shouldn’t use a trigger when a default constraint will do:

We want to spend our SQL Server licensing dollars wisely, so why ask it to do unnecessary work? More CPU time, more IO, and our client is waiting longer for the process to complete (I don’t like making anyone wait).

There’s a second “gotcha” with the AFTER INSERT method that applies to only some use cases. Let’s say you’re loading some historical data into the table, and that data includes the LastModified date. Or maybe your application has a very specific date that should be inserted into the table for this field.

Andy makes good points.

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Constraints On Temp Tables

Kenneth Fisher argues that you should use default naming for temp table constraints: You should be able to create a #temp in every session. That’s the idea, right? It’s one of the things that differentiates a global temp table from a local temp table. But there can be some difficulties with that. If you are working with reusable […]

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Operator Precedence In Complex Check Constraints

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