Simplified Order Of Operations

Kevin Feasel

2016-07-22

T-SQL

Michael J. Swart looks at how SQL Server implements order of operations:

I have a book on my shelf called Practical C Programming published by O’Reilly (the cow book) by Steve Oualline. I still love it today because although I don’t code in C any longer, the book remains a great example of good technical writing.

That book has some relevance to SQL today. Instead of memorizing the full list of operators and their precedence, Steve gives a practical subset:

    1. * (Multiply), / (Division)
    2. + (Add), – (Subtract)

Put parentheses around everything else.

Parentheses, even when unnecessary, are usually a good idea.  They help the reader understand what was going through your mind at the time.

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