Order Of Execution With SQL Server

Kevin Feasel

2017-12-21

Syntax

Andrew Tobin explains the order of how a SQL statement gets processed:

For a particular query you may have the following components and they act in this order:

1 FROM / JOIN
2 WHERE
3 GROUP BY
4 HAVING
5 SELECT
6 ORDER BY
7 TOP / OFFSET-FETCH

Read on for more details.  This is why, for example, you can use an aliased column or calculation in the ORDER BY clause but not in the WHERE clause.

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