Unless the underlying column is not nullable and has no default value
this is only a guess, form designer can change it

Change-Id: Ifa403e00b21fdaf86aef383503d54879b25ac62b
Reviewed-on: https://gerrit.libreoffice.org/62969Reviewed-by: Lionel Elie Mamane <lionel@mamane.lu>
Tested-by: Lionel Elie Mamane <lionel@mamane.lu>