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Explain the ACID properties of a transaction
Ans: ACID properties are a significant concept for databases. The ACID stands for Atomicity, Consistency, Isolation, and Durability.
Atomicity: Atomicity means either all operations of transaction are reflected properly in the database or none are.
Consistency: Consistency means execution of a transaction in isolation (that is with no other transaction executing concurrently) preserves the consistency of the database
Isolation: Although multiple transactions may execute concurrently the system assures that for each pair of transaction Ti and Tj, it appears to Ti that either Tj that either Tj finished execution previous to Ti started or Tj started execution after Ti finished. So each transaction is unaware of other transactions executing simultaneously in the system.
Durability: later than a transaction completes successfully, the changes it has made to the database persist, even if there are system failures.
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