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Hello I made a form in php with db in mysql and when I use it works but when I reload the page send the data I send previously and the records are duplicated please can you help me?
some images: that's how the form looks
this is the code: code
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Send 303 code on the same page to the client after first submit, client won't be able to submit it again with "reload" button.
header("Location: $url", true, 303); die; # where $url is your page