how to protect from duplicate posts in wordpress

i have a tube sites…

What is a tube site?

tube site is a video site like YouTube…
in my site i show videos by putting embed code of the video.
i need to be protect from duplicate post with the same embed code (video).
i cant remember what i already post and what not.. so..

I don’t think there is any way to do this in less you hire someone.

Please try one of the following sites:

• https://jobs.wordpress.net/
• https://directory.codepoet.com/