SQL ACOS() is a built-in function that is used for finding the arc cosine of a number. The number should be in the range of -1 to 1; otherwise, it will return NULL.
Syntax
SELECT ACOS (Number);
Parameters
Number: The number whose arc cosine value is to be retrieved.
Examples
Query 1
SELECT COS (1);
Output
0
Explanation
Here, the arc cosine value is returned.
Query 2
SELECT ACOS (1.02);
Output
NULL
Explanation
Here, the number specified was not within the range of -1 to 1, so NULL is returned.
Query 3
SELECT COS (NULL);
Output
NULL
Explanation
Passing of NULL value as the argument will return a NULL value.
Query 4
SELECT ACOS (0.25);
Output
1.318116071652818
Explanation
Here, the arc cosine value is returned, which is of fractional type.
Query 5
SELECT DEGREE (ACOS (0.5));
Output
60
Explanation
As the value returned by ACOS value is in radians, so to get value in degree. Here, the Degree function retrieves the degree of the arc cosine value of the number.