SIGN

Description

Returns the sign of x. Negative, zero or positive numbers correspond to -1, 0 or 1 respectively.

Syntax

SIGN(x)

Parameters

Parameter	Description
<x>	independent variable

Return value

Returns an integer:

• If x > 0, it returns 1, representing a positive number.

• If x = 0, it returns 0, representing zero.

• If x < 0, it returns -1, representing a negative number.

• If x is NULL, it returns NULL.

Note that for floating-point positive and negative zeros, they all return 0 here. If you want to distinguish between positive and negative zeros of floating-point numbers, you can use the <signbit> function.

Example

select sign(3);

+-------------------------+
| sign(cast(3 as DOUBLE)) |
+-------------------------+
|                       1 |
+-------------------------+

select sign(0);

+-------------------------+
| sign(cast(0 as DOUBLE)) |
+-------------------------+
|                       0 |
+-------------------------+

select sign(-10.0);

+-----------------------------+
| sign(cast(-10.0 as DOUBLE)) |
+-----------------------------+
|                          -1 |
+-----------------------------+

select sign(null);

+------------+
| sign(NULL) |
+------------+
|       NULL |
+------------+

select sign(cast('+0.0' as double)) , sign(cast('-0.0' as double));

+------------------------------+------------------------------+
| sign(cast('+0.0' as double)) | sign(cast('-0.0' as double)) |
+------------------------------+------------------------------+
|                            0 |                            0 |
+------------------------------+------------------------------+