SIGN(a) 
SIGN(a) is an arithmetic function, which provides information about the sign of an expression a (a is a number).
a |
Result of the SIGN(a) Function |
|---|---|
a<0 |
-1 |
a=0 |
0 |
a>0 |
1 |
a is a NULL value |
NULL value |
a is a special NULL value |
Special NULL Value |