1.21.0 additional field as Number type is created as varchar and cannot be sort by number correctly

[elmotofan]

Hi,
Since we are using fields plugin, ever extra field created as "Number" type in GLPI, we cannot sort correctly in the views and queries.
We saw that the field is create as VARCHAR in the database. That cannot be able to sort as number, the sort is made as text in differents view.

That affect to all queries made from differents sources (gui, api, sql, etc)

If cannot be changed by the internal design, may be can be added some function in the code like a "CAST ( xxx as Unsigned)" or similar.

Thanks, and I look forward to any questions.