Alias (SQL): Difference between revisions

Revision as of 14:44, 31 October 2011

Revision as of 11:14, 28 September 2012

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An alias is a feature of SQL that is supported by most, if not all, [[RDBMS|relational database management systems (RDBMSs)]].

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Aliases provide [[Databasedatabase administrator|Database Administrators (DBAs)]]s, as well as other database users, with two things:

# Reduces the amount of code required for a query, and

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# Column aliases

You can give another name to a table (for the duration of the [[Select (SQL)|SELECT query]]) by using an alias.

''This does not rename the database table!''

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A column alias is similar:

SELECT d.DepartmentId AS Id, d.DepartmentName AS Name FROM Department d

In the returned [[result setsset]]s, the data shown above would be returned, with the only exception being "DepartmentID" would show up as "Id", and "DepartmentName" would show up as "Name".

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Also, if only one table is being selected and the query is not using [[Join (SQL)|table joins]], it is permissible to omit the table name or table alias from the column name in the SELECT statement. Example as follows: