microsoft sql keeping a variable without selecting it code example
Example 1: sql declare variable
-- Declare the variable to be used.
DECLARE @MyCounter int;
-- Initialize the variable.
SET @MyCounter = 0;
Example 2: variables in select statement in sql server
USE AdventureWorks2014;
GO
DECLARE @MyVariable int;
SET @MyVariable = 1;
-- Terminate the batch by using the GO keyword.
GO
-- @MyVariable has gone out of scope and no longer exists.
-- This SELECT statement generates a syntax error because it is
-- no longer legal to reference @MyVariable.
SELECT BusinessEntityID, NationalIDNumber, JobTitle
FROM HumanResources.Employee
WHERE BusinessEntityID = @MyVariable;