Most of the time people ask duplicate questions, or the same question.I have seen many questions of Stack OverFlow users comments " this is a duplicate" ,"exact duplicate", and the question is closed.It could be better if the question is filtered before asking rather than giving the users related questions.Something like "These are the exact words of the question asked before" after entering the question OR like " please enter your question and check whether asked before", OR "DID you GOOGLE this question" I have seen this option in many websites with query related.Correct me if I am wrong or any better solutions is appreciated.
Presumably the poster is ignoring the suggestions given when the user types in the question title. Why would they pay attention to a differently worded message?
If you propose to put up a message box or extra page people will just click through it, seeing it as a unnecessary barrier to the important bit - which is posting their question.
People also click through the prompts when answering their own question or posting a second answer to a question, so this sort of prompt doesn't work.
Stack Overflow is designed to have low barriers to entry. The existing mechanisms of flagging and voting to close seem to work well.
Additionally, it can help Google (or Bing) searchers if the same question has been asked a number of times with different wordings. As long as they all point back to the same master question there's not a problem.
Hmm... interesting proposition.
Well, one thing The Builders wanted to avoid when they built SOFU was having to do too much moderation. So if there's any sort of question filter, it'd have to be community policed.
It might be possible to implement something similar to slashdot's firehose. This would be a temporary staging area where questions are posted and voted on; those that "made the cut" eventually would make it to the main page.
But that's kinda against the spirit of SOFU in general, which is "ask a question, get an answer". If the questions are over-moderated, that spirit might be broken.
If it's done, and I'm still on the fence about it, it should be extremely temporary -- on the order of minutes -- and there should be no minimum vote requirement. Instead, it would be a short term list that would allow those with sufficient rep to vote to close if necessary.