Re: Patch: add timing of buffer I/O requests

On Tue, Apr 10, 2012 at 6:32 PM, Peter Geoghegan <peter(at)2ndquadrant(dot)com> wrote:
> On 10 April 2012 23:07, Greg Smith <greg(at)2ndquadrant(dot)com> wrote:
>> On 04/10/2012 12:27 PM, Tom Lane wrote:
>> I am doing more sophisticated things with it, so I'll celebrate this as my
>> opportunity to say I did something you didn't see coming for 2012.
>
> This is why I requested that we expose the query_id hash value - I
> believe that it will be generally useful in clustering situations. It
> would be nice to have a persistent identifier. While we're discussing
> revising pg_stat_statement's interface, are you still opposed to
> exposing that value, Tom?

If people need something like that, couldn't they create it by hashing
the normalized query text with an arbitrary algorithm?

The only obvious advantage of exposing the value used internally is
that it might be helpful in terms of understanding the collision
behavior. But hopefully collisions are pretty rare anyway, so...

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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