SQL Alias
With SQL, an alias name can be given to a table or to a column.
SQL Alias
You can give a table or a column another name by using an alias. This can be
a good thing to do if you have very long or complex table names or column names.
An alias name could be anything, but usually it is short.
SQL Alias Syntax for Tables
SELECT column_name(s)
FROM table_name
AS alias_name
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SQL Alias Syntax for Columns
SELECT column_name AS alias_name
FROM table_name
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Alias Example
Assume we have a table
called "Persons" and another table called "Product_Orders". We will give the
table aliases of "p" an "po" respectively.
Now we want to list all the orders that "Ola Hansen" is responsible for.
We use
the following SELECT
statement:
SELECT po.OrderID, p.LastName, p.FirstName
FROM Persons AS p,
Product_Orders AS po
WHERE p.LastName='Hansen'
WHERE p.FirstName='Ola'
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The same SELECT
statement without aliases:
SELECT Product_Orders.OrderID, Persons.LastName, Persons.FirstName
FROM Persons,
Product_Orders
WHERE Persons.LastName='Hansen'
WHERE Persons.FirstName='Ola'
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As you'll see from the two SELECT statements above; aliases can make queries easier to
both write and to read.
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