hardDSA

What is a deadlock and how do you prevent it?

Q: What is a deadlock and how do you prevent it?

A **deadlock** occurs when two transactions each hold a lock the other needs, so neither proceeds; the DB detects it and aborts one. Prevent by accessing tables/rows in a consistent order, keeping transactions short, lowering isolation where safe, and adding retry logic.

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Explain deadlocks.

deadlock

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A deadlock occurs when two transactions each hold a lock the other needs, so neither proceeds; the DB detects it and aborts one. Prevent by accessing tables/rows in a consistent order, keeping transactions short, lowering isolation where safe, and adding retry logic.

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