Jean-Yves : yes it works, i rarely use it because i lost precision in taxes calculation, but the last calculation in the query i should use it to avoid that strange number 
Norman : it return a number if you ask a number, but you can insert anything in a real / integer column. MySQL and PostGres you can’t insert a string in a number column
Sure but that doesn’t mean it uses strings
Just that it does not enforce typing in the same way postgres etc do