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SQL QuizSQL 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
FROM table_name
AS alias_name
SQL Alias Syntax for Columns
FROM table_name
Alias Example
Assume we have a table called "Persons" and another table called "Product_Orders". We will give the table aliases of "p" and "po" respectively.
Now we want to list all the orders that "Ola Hansen" is responsible for.
We use the following SELECT statement:
FROM Persons AS p,
Product_Orders AS po
WHERE p.LastName='Hansen' AND p.FirstName='Ola'
The same SELECT statement without aliases:
FROM Persons,
Product_Orders
WHERE Persons.LastName='Hansen' AND Persons.FirstName='Ola'
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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