Re: Read Uncommitted

Many will want to use it to do aggregation, e.g. a much more efficient COUNT(*), because they want performance and don't care very much about transaction consistency. E.g. they want to compute SUM(sales) by salesperson, region for the past 5 years, and don't care very much if some concurrent transaction aborted in the middle of computing this result.

On 12/18/19, 2:35 PM, "Stephen Frost" <sfrost(at)snowman(dot)net> wrote:

Greetings,

* Robert Haas (robertmhaas(at)gmail(dot)com) wrote:
> On Wed, Dec 18, 2019 at 1:06 PM Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
> > Just consider this part of the recovery toolkit.
>
> I agree that it would be useful to have a recovery toolkit for reading
> uncommitted data, but I think a lot more thought needs to be given to
> how such a thing should be designed. If you just add something called
> READ UNCOMMITTED, people are going to expect it to have *way* saner
> semantics than this will. They'll use it routinely, not just as a
> last-ditch mechanism to recover otherwise-lost data. And I'm
> reasonably confident that will not work out well.

+1.

Thanks,

Stephen