By the way, I found http://127.0.0.1:8000/examples/static/epydoc/index.html also have such document. But, I missed it. I should click on the left upper corner to choose validator at first to narrow the display results.
On 6月4日, 下午4時15分, dlin <dlin...@gmail.com> wrote: > Thanks, It works. > > I've searched it onhttp://web2py.com/book/default/section/7/4 > > On 6月4日, 下午1時47分, Yarko Tymciurak <resultsinsoftw...@gmail.com> wrote: > > > > > On Jun 3, 11:31 pm, dlin <dlin...@gmail.com> wrote: > > > > There is a field which I want user to enter different answer, or just > > > keep in empty. > > > empty, or unique answer: > > > db.table.answer.requires=IS_NULL_OR( IS_NOT_IN_DB( db, > > 'table.answer' ) ) > > > > I've tried by: > > > > db.table.field.requires=IS_NOT_IN_DB(db, 'table.field') > > > > But, it will failed, if the second empty field entered. > > > > How could I do the validation for this case? > > > Is there any method?