Returns the sign (positive or negative) of the given number.
SIGN( numeric-expression )
numeric-expression The number for which the sign is to be returned. numeric-expression may be of type INTEGER, DOUBLE, or NUMERIC.
SMALLINT
For negative numbers, the SIGN function returns -1.
For zero, the SIGN function returns 0.
For positive numbers, the SIGN function returns 1.
SQL/2008 Vendor extension.
The following statement returns the value -1
SELECT SIGN( -550 );