AND (TransactSQL)
Combines two Boolean expressions and returns TRUE when both expressions are TRUE. When more than one logical operator is used in a statement, the AND operators are evaluated first. You can change the order of evaluation by using parentheses.
TransactSQL Syntax Conventions
Syntax
boolean_expression AND boolean_expression
Arguments
 boolean_expression
Is any valid expression that returns a Boolean value: TRUE, FALSE, or UNKNOWN.
Result Types
Boolean
Result Value
Returns TRUE when both expressions are TRUE.
Remarks
The following chart shows the outcomes when you compare TRUE and FALSE values by using the AND operator.

TRUE 
FALSE 
UNKNOWN 

TRUE 
TRUE 
FALSE 
UNKNOWN 
FALSE 
FALSE 
FALSE 
FALSE 
UNKNOWN 
UNKNOWN 
FALSE 
UNKNOWN 
Examples
A. Using the AND operator
The following example selects information about employees who have both the title of Marketing Assistant and more than 41 vacation hours available.
USE AdventureWorks2012;
GO
SELECT BusinessEntityID, LoginID, JobTitle, VacationHours
FROM HumanResources.Employee
WHERE JobTitle = 'Marketing Assistant'
AND VacationHours > 41 ;
B. Using the AND operator in an IF statement
The following examples show how to use AND in an IF statement. In the first statement, both 1 = 1 and 2 = 2 are true; therefore, the result is true. In the second example, the argument 2 = 17 is false; therefore, the result is false.
IF 1 = 1 AND 2 = 2
BEGIN
PRINT 'First Example is TRUE'
END
ELSE PRINT 'First Example is FALSE';
GO
IF 1 = 1 AND 2 = 17
BEGIN
PRINT 'Second Example is TRUE'
END
ELSE PRINT 'Second Example is FALSE' ;
GO