* Old precision issue. New results matching server results now
* Value overflow issue. New result matching server result now
* Showing correct column name now
* Added --disable_warning to subpress warnings that cause result mismatched
* Need to add one more result file
In this patch, we set the unioned type to a wide decimal, if any of the
numeric columns involved in the union operation have a precision > 18
(which is also possible for BIGINT/UBIGINT types) and <= 38.