Practice mode DBMS and SQL

What does strict two-phase locking add to basic 2PL, and what problem does it remove?

Correct answer B. Exclusive locks are held until commit or abort, which removes cascading aborts

Explanation

Under basic 2PL a transaction can release a write lock early, so another transaction may read the uncommitted value and must abort if the writer aborts: a cascading abort. Strict 2PL keeps exclusive locks until the transaction ends, so nobody reads uncommitted writes. Rigorous (strong strict) 2PL holds all locks to the end. Neither variant prevents deadlocks; that needs detection or prevention.

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What does strict two-phase locking add to basic 2PL, and what problem does it remove?

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What does strict two-phase locking add to basic 2PL, and what problem does it remove?

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