If you do know the user-name, then you just need a "user-likes" table where "user-ID" and "topic-ID" are the primary key. Attempt to insert a row. If a matching row already exists, the insert will fail ... and you simply ignore it.

In reply to Re: How to avoid mulitple submission of form in html by Anonymous Monk
in thread How to avoid mulitple submission of form in html by romy_mathew

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