Demystifying Database Transactions
The most compelling feature of relational database systems is ACID(Atomicity Consistency Isolation Durability). Isolation is achieved using transactions. Isolation is needed to avoid race conditions when concurrent actors act upon the same row.
SQL standard defines isolation with different levels. Every isolation level offers certain guarantees and possible anomalies that can occur. Understanding the internals of isolation levels and their anomalies helps us identify the right level for the use case and work with the anomalies.
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