Product and version: FileMaker Pro 17.0.4
OS and version: all
When working with ESS tables from a MySQL database, FileMaker will mark every field that has the type "integer" as "Numeric only". This can of course not be changed in FileMaker. Changing the field type in MySQLfrom "integer" to "text" or "varchar" and synching the table in FileMaker, FM will recognize the changed format and show the field type correctly as "text", but the validation restriction "numeric only" will remain in place.
How to replicate
Have a MySQL table with a field of type "integer". Connect via ODBC and link the table to a filemaker solution. Database manager will show the field as "Number, Always validate, numeric only".
In MySQL change the data type of the field to "varchar" and save. Synch the table in FileMaker. Database manager will show the field as "Text, Always validate, numeric only".