What types of errors do different levels of transaction isolation prevent?
sobes.tech AI
Answer from AI
Transaction isolation levels determine which types of errors or anomalies they prevent:
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READ UNCOMMITTED — the lowest level of isolation. Allows seeing uncommitted changes of other transactions, which can lead to "dirty reads".
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READ COMMITTED — prevents dirty reads, as the transaction only sees committed changes. However, non-repeatable reads and phantom reads are possible.
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REPEATABLE READ — prevents non-repeatable reads, ensuring that data read in a transaction does not change until it completes. However, phantom reads can occur.
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SERIALIZABLE — the strictest level, prevents all the listed anomalies, including phantom reads, providing full transaction isolation but reducing concurrency.
Thus, the choice of isolation level depends on the balance between data integrity and performance.