The ATAN2 function returns the arc tangent value of y/x in radian. This function is working like the ATAN Function. Arguments x and y must be specified. The return value is a DOUBLE type.
ATAN2 ( y, x )
SELECT ATAN2(1,1), ATAN2(-1,-1), ATAN2(Pi(),0);
atan2(1, 1) atan2(-1, -1) atan2( pi(), 0)
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7.853981633974483e-01 -2.356194490192345e+00 1.570796326794897e+00