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Identify proper SELECT query structure
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Logical Processing Order of the
SELECT statement
The following steps show the logical processing order, or
binding order, for a SELECT statement. This order determines when the objects
defined in one step are made available to the clauses in subsequent steps. For
example, if the query processor can bind to (access) the tables or views
defined in the FROM clause, these objects and their columns are made available
to all subsequent steps. Conversely, because the SELECT clause is step 8, any
column aliases or derived columns defined in that clause cannot be referenced
by preceding clauses. However, they can be referenced by subsequent clauses
such as the ORDER BY clause. Note that the actual physical execution of the
statement is determined by the query processor and the order may vary from this
list.
FROM
ON
JOIN
WHERE
GROUP
BY
WITH
CUBE or WITH ROLLUP
HAVING
SELECT
DISTINCT
ORDER
BY
TOP
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- 70-761 (Create database programmability objects by using TSQL) SQL Server Querying Data with Transact-SQL Apunte sobre Identify proper SELECT query structure, creado por Dean West el 22/03/2017.
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- Dean West
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