The SQRT numeric function returns the square root of a given number.
SQRT returns the square root of source_number. The parameter can be any built-in numeric data type. The result is a FLOAT. If the parameter is NULL, the result is NULL.
SQRT(4)
returns 2E+1 SQRT(2)
returns 1.414213562373095E+0 SQRT(-1)
throws
an exception.