Re: Avoid MVCC using exclusive lock possible?

Jon Jensen wrote:
> How would you do a rollback if an error occurred mid-query? How would you
> keep your table from being a big pile of junk if a power failure happened
> during the query?

As most non-MVCC database do: by writing WAL records.

In theory, it seems to me that we could implement an overwriting 
storage manager for PostgreSQL (i.e. we'd have both MVCC and non-MVCC, 
and allow users to choose at runtime). It would require a *lot* of 
work, but I can't see any fundamental reason why it wouldn't be possible.

-Neil