Questions tagged [lost-update]

Can somebody explain me whats exactly the difference between a 'lost update' and a 'write skew' in database transaction theory? Can somebody give me an example?

I'm reading A Critique of ANSI SQL Isolation Levels and get confused by the two definitions: Dirty write w1[x]...w2[x]...((c1 or a1) and (c2 or a2) in any order) Lost update r1[x]...w2[x]...w1[x]...c1 Doesn't the history definition of lost…

A lost update occurs when two different transactions are trying to update the same column on the same row within a database at the same time. Typically, one transaction updates a particular column in a particular row, while another that began…

On page 52 of PostgreSQL 14 Internals, Egor Rogov indicates that "lost updates" can occur with the "Read Committed" isolation level. There is also a sentence that reads: But in some cases, there is a risk of losing changes at the Read Committed…