In computer science, in the field of Databases, Write-Write Conflict, also known as overwriting commit (data management) data is a computational anomaly associated with interleaved execution of Database transaction.

Given a Schedule (computer science) H

H = egin{bmatrix} T1 & T2 \ W(A) & \ & W(B) \ W(B) & \ Com. & \ & W(A)\ & Com. end{bmatrix}

note that there is no read in this schedule. 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/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 serialize.

Strict two-phase locking, overcomes this inconsistency by locking T1 out from B. Unfortunately, deadlocks is something Strict 2PL does not overcome all the time.