Dynamic Searches In SQL

Kevin Feasel

2017-02-28

T-SQL

Kenneth Fisher looks at a few methods for dynamic searches in T-SQL:

Multiple Queries

Pro: We get a separate query plan for each combination of parameters so performance is great. (Well, as good as can be anyway.)
Con: Maintance stinks. We need 16 different queries when we have 4 parameters and the numbers increase dramatically as we add additional parameters. So any change we make to the base query will have to be changed 16 times, and/or adding a new parameter means careful logic and adding a bunch of new queries.

I’d consider this a gateway for Erland Sommarskog’s article on the topic.

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