func (m *Mapping) ColumnFields(exclude ...string) []*Field {
	fields := []*Field{}

	for _, field := range m.Fields {
		if shared.StringInSlice(field.Name, exclude) {
			continue
		}
		if field.Type.Code == TypeColumn {
			fields = append(fields, field)
		}
	}

	return fields
}
func (m *Mapping) ColumnFields(exclude ...string) []*Field {
	fields := []*Field{}

	for _, field := range m.Fields {
		if shared.StringInSlice(field.Name, exclude) {
			continue
		}
		if field.Type.Code == TypeColumn {
			fields = append(fields, field)
		}
	}

	return fields
}
// ColumnFields returns the fields that map directly to a database column,
// either on this table or on a joined one.