This function is safe to use with BIGINT  values. 

• ACOS( X ) 

-> 32 

Returns the arc cosine of X , that is, the value whose cosine is X . Returns NULL  if X  is not in the range -1 to 1 . 

mysql> SELECT ACOS(1); -> 0 mysql> SELECT ACOS(1.0001); -> NULL mysql> SELECT ACOS(0); -> 1.5707963267949 

• ASIN( X ) 

Returns the arc sine of X , that is, the value whose sine is X . Returns NULL  if X  is not in the range -1  to 1 . 

mysql> SELECT ASIN(0.2); -> 0.20135792079033 mysql> SELECT ASIN(’foo’); +-------------+ | ASIN(’foo’) | +-------------+ | 0 | +-------------+ 1 row in set, 1 warning (0.00 sec) mysql> SHOW WARNINGS; +---------+------+-----------------------------------------+ | Level | Code | Message | +---------+------+-----------------------------------------+ | Warning | 1292 | Truncated incorrect DOUBLE value: ’foo’ | +---------+------+-----------------------------------------+ 

• ATAN( X ) 

Returns the arc tangent of X , that is, the value whose tangent is X . 

mysql> SELECT ATAN(2); -> 1.1071487177941 mysql> SELECT ATAN(-2); -> -1.1071487177941 

• ATAN( Y , X ) , ATAN2( Y , X ) 

Returns the arc tangent of the two variables X  and Y . It is similar to calculating the arc tangent of Y  / X , except that the signs of both arguments are used to determine the quadrant of the result. 

mysql> SELECT ATAN(-2,2); -> -0.78539816339745 mysql> SELECT ATAN2(PI(),0); -> 1.5707963267949 

• CEIL( X ) 

CEIL()  is a synonym for CEILING() . 

• CEILING( X ) 

Returns the smallest integer value not less than X . 

