Assignment Operator (Transact-SQL)
The equal sign (=) is the only Transact-SQL assignment operator. In the following example, the @MyCounter variable is created, and then the assignment operator sets @MyCounter to a value returned by an expression.
DECLARE @MyCounter INT; SET @MyCounter = 1;
The assignment operator can also be used to establish the relationship between a column heading and the expression that defines the values for the column. The following example displays the column headings FirstColumnHeading and SecondColumnHeading. The string xyz is displayed in the FirstColumnHeading column heading for all rows. Then, each product ID from the Product table is listed in the SecondColumnHeading column heading.
USE AdventureWorks2008R2; GO SELECT FirstColumnHeading = 'xyz', SecondColumnHeading = ProductID FROM Production.Product; GO