usage-rules/ecto.md
message.user.emailimport Ecto.Query and other supporting modules when you write seeds.exsEcto.Schema fields always use the :string type, even for :text, columns, ie: field :name, :stringEcto.Changeset.validate_number/2 DOES NOT SUPPORT the :allow_nil option. By default, Ecto validations only run if a change for the given field exists and the change value is not nil, so such as option is never neededEcto.Changeset.get_field(changeset, :field) to access changeset fieldsuser_id, must not be listed in cast calls or similar for security purposes. Instead they must be explicitly set when creating the structmix ecto.gen.migration migration_name_using_underscores when generating migration files, so the correct timestamp and conventions are applied