Sql variable null check

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All Rights Reserved. W3Schools is Powered by W3. Learn more. Ask Question. Asked 5 years, 4 months ago. Active 5 years, 4 months ago. Viewed 12k times. Effectively, if myIdParam is null, we do not want to restrict the results using this parameter. Is there a way to optimize this so the check is done only once at runtime? Improve this question. Mystagogue Mystagogue 1 1 gold badge 2 2 silver badges 6 6 bronze badges. Look at this answer: stackoverflow.

Considering this question is really about optional parameters, I'd say it's a duplicate of the one you linked. Probably, but it's a post from 6 years ago. Maybe with SqlServer or there's a new approach. I tested it on without recompile and took forever — vercelli. Since your actual query has many optional parameters, dynamic SQL will provide the best performance.

See sommarskog. I consider this the best option for balancing performance and readability. Add a comment. Active Oldest Votes. Improve this answer. The second checks for a magic value that may or may not occur in the data 'false'.

Best practice is to avoid magic values. HABO I agree that we should avoid "magic" values at all cost and first approach is preferred. EzLo EzLo Sign up or log in Sign up using Google. Sign up using Facebook. Sign up using Email and Password. Post as a guest Name. Email Required, but never shown. The Overflow Blog. Podcast Helping communities build their own LTE networks. Podcast Making Agile work for data science.