Information Design Tool number format

I have a problem with the information design tool and concerns the representation of the number format as well as the removing by decimal separator.

The Information Design Tool uses a MS SQL server 2014 with an ODBC connection. All database columns own the data type "FLOAT". In the relational connection the column values are correctly shown (decimal separator is a comma). However, all decimal separators are removed from the data basis and therefore the numerical values are shown wrong. How is able prevented that the decimal separators are removed?