SQL - Transactions and Data IntegrityWhich transaction isolation level prevents dirty reads but allows non-repeatable reads and phantom reads?ARepeatable ReadBRead CommittedCRead UncommittedDSerializableCheck Answer
Step-by-Step SolutionSolution:Step 1: Understand dirty readsDirty reads happen when a transaction reads uncommitted changes from another transaction.Step 2: Identify isolation level preventing dirty readsRead Committed prevents dirty reads but allows non-repeatable and phantom reads.Final Answer:Read Committed -> Option BQuick Check:Dirty reads prevented = Read Committed [OK]Quick Trick: Read Committed blocks dirty reads but not phantoms [OK]Common Mistakes:Confusing Read Committed with Repeatable ReadThinking Read Uncommitted prevents dirty reads
Master "Transactions and Data Integrity" in SQL9 interactive learning modes - each teaches the same concept differentlyLearnWhyDeepVisualTryChallengeProjectRecallTime
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