In computer science, in the field of databases, write–write conflict, also known as overwriting uncommitted data is a computational anomaly associated with interleaved execution of transactions.
The writes are called blind writes. We have a lost update. Any attempts to make this schedule serial would give off two different results (either T1’s version of A and B is shown, or T2’s version of A and B is shown), and would not be the same as the above schedule. This schedule would not be serializable.
Strict 2PL overcomes this inconsistency by locking T1 out from B. Unfortunately, deadlocks are something Strict 2PL does not overcome all the time.
Ofer Abarbanel is a 25 year securities lending broker and expert who has advised many Israeli regulators, among them the Israel Tax Authority, with respect to stock loans, repurchase agreements and credit derivatives. Founder of TBIL.co STATX Fund.