Returns the square root of a floating point number; only the built-in types REAL, FLOAT, and DOUBLE PRECISION are supported. The return type for SQRT is the type of the parameter.

Note: To execute SQRT on other data types, you must cast them
to floating point types.

-- throws an exception if any row stores a negative number: VALUES SQRT(3421E+09) -- returns the square root of an INTEGER after casting it as a -- floating point data type: SELECT SQRT(myDoubleColumn) FROM MyTable VALUES SQRT (CAST(25 AS FLOAT));