question Re: How to check whether Hive table CBO status? in Archives of Support Questions (Read Only)

How to check whether Hive table CBO status?

rxu — Thu, 21 Jan 2016 06:10:56 GMT

We suspect a Hive table CBO statistics is incorrect. How can we check it and how to re-compute them, should we run the commands again?

analyze table t compute statistics;
analyze table t compute statistics for columns;

Re: How to check whether Hive table CBO status?

yzhang1 — Fri, 22 Jan 2016 07:15:45 GMT

usually explain a query on the table or describe formatted on the table shows whether stats is 'accurate'. can also do describe formatted xxx column xxx; to have an idea if it is correct or not on the column

Re: How to check whether Hive table CBO status?

nsabharwal — Fri, 22 Jan 2016 12:25:16 GMT

@rxu

and Its ok run compute stats anytime except peak hours.