What does <> (angle brackets) mean in MS-SQL Server?
<> operator means not equal to in MS SQL.
It compares two expressions (a comparison operator). When you compare nonnull expressions, the result is TRUE if the left operand is not equal to the right operand; otherwise, the result is FALSE. If either or both operands are NULL, see the topic SET ANSI_NULLS (Transact-SQL).
See here : Not Equal To
Also check :
1) Not equal <> != operator on NULL2) Testing for inequality in T-SQL