Edit conflict

An edit conflict is a computer problem where multiple editors cannot all edit the same item during a short time period. The problem is encountered on or distributed data systems. An edit conflict occurs when a shared document is being edited by more than one person at the same time, and the attempted changes are treated as incompatible with each other. One person attempts to edit the document, but upon trying to save the new version, another person has already modified the document in the intervening time period, thus causing a difference between the attempted edit and the already-made edit that must be resolved manually, and causing an "edit conflict" error message. Computer writer Gary B. Shelly notes that many systems "will block the contributor who is attempting to edit the page from being able to do so until the contributor currently editing the page saves changes or remains idle on the page for an extended period of time."

Edit conflicts can also arise when two or more editors are working on Google Sites, or when two or more users simultaneously edit the same file in a revision control system which does not have file locking.

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