SQL Server/T-SQL Tutorial/Math Functions/SIGN
SIGN returns a -1 if the number is negative, +1 if the number is positive, or 0 if the number is 0.
<source lang="sql">
4> SELECT SIGN(-23) 5> GO
-1
(1 rows affected)</source>
<source lang="sql">
4> SELECT SIGN(-23) 5> GO
-1
(1 rows affected)</source>