On Mon, 2020-07-13 at 13:01 +0530, Rama Krishnan wrote: > I m preparing for interview one of the recruiter asked me mvcc drawbacks as i > told due > to mvcc it use more space and need to perform maintenance activity.
Yes. Generally speaking, you have to pay a price for keeping old versions of the data around, no matter how you implement it. > Another one is the same data causes an update conflict because two different > transactions > can update the same version of the row. > he told its wrong, kindly tell me will you please tell me its correct or > wrong? There is always a certain version (the latest) that can be updated, so this is the same no matter if you have MVCC or not: if two sessions want to update the same row, one has to wait until the other is done. Yours, Laurenz Albe -- Cybertec | https://www.cybertec-postgresql.com
