Stats refresh

Analytics

Stats refresh

Hi, I've collected stats on a table at table level expecting the stats to be refreshed on the columns (which were defined earlier).. however stats were refreshed on only few columns.. can somebody please tell me if I'm missing anything??
3 REPLIES
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Teradata Employee

Re: Stats refresh

What does the show statistics tell you?

 

Are there any defined user change or percent thresholds?

 

What about system wide settings for those?

 

The optimizer should skip recollection if some of those settings are set and not met.

 

Dave

Re: Stats refresh

Thanks David, My observation is that if there are no changes in the number of unique values in a column for a table, stats will not be updated (even if you collect stats on the whole table).

Teradata Employee

Re: Stats refresh

Carrie Ballinger has written some great material on how auto stats collection decisions are made. Search this community for her blogs/docs.