What causes a deadlock, and how do databases resolve it?
A deadlock happens when transaction A holds a lock transaction B needs, while B holds a lock A needs — neither can proceed. Databases detect this with a wait-for graph (a cycle means deadlock) and resolve it by picking a victim transaction to abort and retry, rather than letting both wait forever.
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Database Transactions Explained: ACID, Isolation Levels, and Concurrency ControlWhat ACID actually guarantees, and how pessimistic vs optimistic concurrency control decide whether your app locks or retries under load.
Read the full analysisOther questions this article answers
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