SQL SIGN() function returns the sign of a number.

**SQL SIGN()**

SQL SIGN() is a built-in function used for returning the sign of the number. It indicates whether the number is positive or negative by returning the following result: –

- 1 if the number is positive i.e., number>0
- -1 if the number is negative i.e., number<0
- 0 is the number is zero i.e., number=0

**Syntax**

SELECT SIGN (number);

**Parameters**

Number: The number which is used for testing its sign.

**Examples**

**Query 1**

Select Sign (-23);

**Output**

-1

**Explanation**

As the number is less than 0. So, the sign of the number returned was -1.

**Query 2**

Select Sign (0);

**Output**

0

**Explanation**

As the number is equal to 0. So, the sign of the number was returned was 0.

**Query 3**

Select Sign (1);

**Output**

1

**Explanation**

As the number is greater than 0. So, the sign of the number returned was 1.

**Query 4**

Select Sign (0.1);

**Output**

1.0

**Explanation**

As the number is greater than 0 and is in decimal format. The number returned is also in decimal format.

**Query 5**

Select Sign (40-50);

**Output**

-1

**Explanation**

Here, the arithmetic expression is executed in sign function which resulted in a number less than 0. So, the sign of the number is negative.

**Query 6**

Select Sign (NULL);

**Output**

NULL

**Explanation**

As the number **NULL** is given as an input to the function. So, NULL was returned as an output.