Re: REVIEW: Track TRUNCATE via pgstat

Alex Shulgin wrote:

> OK, I think I have now all bases covered, though the updated patch is
> not that "pretty".
> 
> The problem is that we don't know in advance if the (sub)transaction is
> going to succeed or abort, and in case of aborted truncate we need to
> use the stats gathered prior to truncate.  Thus the need to track
> insert/update/deletes that happened before first truncate separately.

Ugh, this is messy indeed.  I grant that TRUNCATE is a tricky case to
handle correctly, so some complexity is expected.  Can you please
explain in detail how this works?

> To the point of making a dedicated pgstat testing tool: let's have
> another TODO item?

Sure.

-- 
Álvaro Herrera                http://www.2ndQuadrant.com/
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