Tutorials References Exercises Videos Menu
Create Website Get Certified Upgrade

SQL Tutorial

SQL HOME SQL Intro SQL Syntax SQL Select SQL Select Distinct SQL Where SQL And, Or, Not SQL Order By SQL Insert Into SQL Null Values SQL Update SQL Delete SQL Select Top SQL Min and Max SQL Count, Avg, Sum SQL Like SQL Wildcards SQL In SQL Between SQL Aliases SQL Joins SQL Inner Join SQL Left Join SQL Right Join SQL Full Join SQL Self Join SQL Union SQL Group By SQL Having SQL Exists SQL Any, All SQL Select Into SQL Insert Into Select SQL Case SQL Null Functions SQL Stored Procedures SQL Comments SQL Operators

SQL Database

SQL Create DB SQL Drop DB SQL Backup DB SQL Create Table SQL Drop Table SQL Alter Table SQL Constraints SQL Not Null SQL Unique SQL Primary Key SQL Foreign Key SQL Check SQL Default SQL Index SQL Auto Increment SQL Dates SQL Views SQL Injection SQL Hosting SQL Data Types

SQL References

SQL Keywords MySQL Functions SQL Server Functions MS Access Functions SQL Quick Ref

SQL Examples

SQL Examples SQL Quiz SQL Exercises SQL Certificate

SQL AS Keyword


AS

The AS command is used to rename a column or table with an alias.

An alias only exists for the duration of the query.


Alias for Columns

The following SQL statement creates two aliases, one for the CustomerID column and one for the CustomerName column:

Example

SELECT CustomerID AS ID, CustomerName AS Customer
FROM Customers;
Try it Yourself »

The following SQL statement creates two aliases. Notice that it requires double quotation marks or square brackets if the alias name contains spaces:

Example

SELECT CustomerName AS Customer, ContactName AS [Contact Person]
FROM Customers;
Try it Yourself »

The following SQL statement creates an alias named "Address" that combine four columns (Address, PostalCode, City and Country):

Example

SELECT CustomerName, Address + ', ' + PostalCode + ' ' + City + ', ' + Country AS Address
FROM Customers;
Try it Yourself »

Note: To get the SQL statement above to work in MySQL use the following:

SELECT CustomerName, CONCAT(Address,', ',PostalCode,', ',City,', ',Country) AS Address
FROM Customers;

Alias for Tables

The following SQL statement selects all the orders from the customer with CustomerID=4 (Around the Horn). We use the "Customers" and "Orders" tables, and give them the table aliases of "c" and "o" respectively (Here we use aliases to make the SQL shorter):

Example

SELECT o.OrderID, o.OrderDate, c.CustomerName
FROM Customers AS c, Orders AS o
WHERE c.CustomerName="Around the Horn" AND c.CustomerID=o.CustomerID;
Try it Yourself »