MySQL Tutorial/Math Numeric Functions/DEGREES
DEGREES(X) returns the argument X, converted from radians to degrees
mysql>
mysql> SELECT DEGREES(PI());
+---------------+
| DEGREES(PI()) |
+---------------+
| 180 |
+---------------+
1 row in set (0.00 sec)
mysql>
mysql> SELECT DEGREES(PI() / 2);
+-------------------+
| DEGREES(PI() / 2) |
+-------------------+
| 90 |
+-------------------+
1 row in set (0.00 sec)
mysql>