How many stats exist for that table?
Single- or multi-column?
What's your Teradata release?
How are the stats recollected, individually or at table level?
Since it is a fairly large table (and hence i'm assuming it to have fair skew) , i would ask recommend you to collect sample stats. We have tables with 54 billion rows and we collect sample stats once every fortnight. I'm surprised to see some of the stats absolutely exact
in 14.10 it's not recommended
There's an Orange Book on the new functionality in TD14.10, additionally have a look at:
Regarding SAMPLE, in most cases this will be OK (in fact the optimizer starts doing sample stats automatically when you don't drop/recreate stats), there's just one special case where you need to take caution:
You can simply do a SHOW STATS VALUES ON column, collect SAMPLE stats (in 14.10 you must specify the sample size), do another SHOW STATS VALUES ON column and compare both. If the sample is too bad, you don't have to recollect full stats again, simply resubmit the result of the 1st SHOW.
Thanks dnoeth for your quick response.
I just want to know the roles and responsibilities of a person in IT industry with respective of Teradata Collect stats..
As a developer I am just using Collect stats on **** Syntax from my end ,what about the DBA responsibility on it..Teradata by default refresh and store the stats information into data dictionaries or any manual process.. In my case my DBA completely working on dbadmin_procs.Stats_Log only,What exactly it is..I tried to access it but don't have access on it..What to do..Can anyone expalin breifly or send any links for this.
Re-collecting stats is not done automatically, there's usually an automated process for it.
In your case this seems to be done based on "dbadmin_procs.Stats_Log" which is not provided by Teradata...