Google Groups no longer supports new Usenet posts or subscriptions. Historical content remains viewable.
Dismiss

Clearing the complete flag

1 view
Skip to first unread message

Roy Hann

unread,
Nov 12, 2009, 8:44:06 AM11/12/09
to
Apart from hacking the scomplete flag in iistatistics is there a
"respectable" way to clear the complete flag on an attribute?

--
Roy

UK Ingres User Association Conference 2010 will be on Tuesday June 8 2010
Go to http://www.iua.org.uk/join to get on the mailing list.


Jean-Pierre Zuate, La Fage Conseil

unread,
Nov 12, 2009, 9:11:20 AM11/12/09
to Ingres and related product discussion forum
Hi Roy,

does it mean your stats are collected with the [optimizedb] -zw flag ?
See http://docs.ingres.com/Ingres/9.2/Command%20Reference%20Guide/optimizedbcmd.htm#o1231

Stats are supposed, by default, "not complete", till the -zw flag is used.

Except deleting stats with statdump and recreate them without this
flag, I don't know ...

HTH ... (but not sure at all).
--
Jean-Pierre Zuate
La Fage Conseil
+33(0)6 11 40 11 09
jean-pie...@lafageconseil.fr
http://lafageconseil.fr/

2009/11/12 Roy Hann <spec...@processed.almost.meat>:

> _______________________________________________
> Info-Ingres mailing list
> Info-...@kettleriverconsulting.com
> http://ext-cando.kettleriverconsulting.com/mailman/listinfo/info-ingres
>

Roy Hann

unread,
Nov 12, 2009, 9:39:25 AM11/12/09
to
Jean-Pierre Zuate, La Fage Conseil wrote:

> Hi Roy,
>
> does it mean your stats are collected with the [optimizedb] -zw flag ?

Yep, that's the one I mean.

> See http://docs.ingres.com/Ingres/9.2/Command%20Reference%20Guide/optimizedbcmd.htm#o1231
>
> Stats are supposed, by default, "not complete", till the -zw flag is used

Well just for clarity, "complete" doesn't refer to the statistics, it
refers to the set of values in the column. If you have a master-detail
relationship then the master key column is complete with respect to the
detail foreign key column; i.e. "complete" implies a referential
integrity constraint. It discourages the optimizer from
underestimating the cardinality of the join. (I don't think the
way the complete flag is interpreted is quite right, but it is helpful
more often than it's harmful, I find.)

> Except deleting stats with statdump and recreate them without this
> flag, I don't know ...

Thanks Jean-Pierre, I was afraid that is the case.

0 new messages