ToDouble

The ToDouble function converts numeric values and numeric strings to the double data byte.

ToDouble(<numeric or numeric string>)

Double

The minimum Double value is 4.9E-324 and the maximum Double value is 1.7976931348623157E308.

select ToDouble(8.8), TypeNameOf(ToDouble(8.8))
from Empty();

select ToDouble('120000.4533'), TypeNameOf(ToDouble('120000.4533'))
from Empty();