Append the same fields to all the tables db._common_fields

|True|# coding: utf8



signature = db.Table(db,'auth_signature',

      Field('created_on','datetime',default=request.now,

            writable=False,readable=False, label=T('Created on')),

        Field('created_by','reference %s' % auth.settings.table_user_name,default=auth.user_id,

            writable=False,readable=False, label=T('Created by')),

        Field('modified_on','datetime',update=request.now,default=request.now,

            writable=False,readable=False, label=T('Modified on')),

      Field('modified_by','reference %s' % auth.settings.table_user_name,

            default=auth.user_id,update=auth.user_id,

            writable=False,readable=False, label=T('Modified by'))

      )



db._common_fields.append(signature) #db._common_fields is a list of fields that should belong to all the tables



db.define_table('category',

    Field('is_enabled', 'boolean', default=True, label=T('Enabled')),

    Field('name', 'string', length=256, label=T('Name')),

    Field('description', 'text', readable=True, writable=True, label=T('Description')),

    format='%(name)s'

)|