beginnerIsolation Levels — Dirty Read, Phantom Read, Non-Repeatable Read

What is the difference between READ COMMITTED and REPEATABLE READ?

READ COMMITTED: each SQL statement sees the most recently committed data at statement start. If Transaction B commits between two SELECT statements in Transaction A, Transaction A's second SELECT sees Transaction B's changes. Prevents dirty reads only. REPEATABLE READ: the entire transaction sees data as of the transaction's start time. Transaction A gets a consistent snapshot: even if Transaction

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