Sergey Shelukhin created HIVE-20434:
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             Summary: analyze on an empty partition doesn't produce correct 
stats
                 Key: HIVE-20434
                 URL: https://issues.apache.org/jira/browse/HIVE-20434
             Project: Hive
          Issue Type: Bug
            Reporter: Sergey Shelukhin
            Assignee: Ashutosh Chauhan


{noformat}
set hive.stats.dbclass=fs;
set hive.stats.fetch.column.stats=true;
set datanucleus.cache.collections=false;
set hive.merge.mapfiles=false;
set hive.merge.mapredfiles=false;
set hive.mapred.mode=nonstrict;

set hive.stats.autogather=true;
set hive.stats.column.autogather=true;
set hive.compute.query.using.stats=true;
set hive.explain.user=false;

set hive.fetch.task.conversion=none;
set hive.query.results.cache.enabled=false;

create table stats_part(key int,value string) partitioned by (p int) 
tblproperties ("transactional"="false");
insert into table stats_part partition(p=101) values (1, "foo");
explain select count(key) from stats_part; -- <== stats are correct

ALTER TABLE stats_part CHANGE COLUMN key key2 int;
explain select count(key2) from stats_part; -- <== stats are now incorrect

analyze table stats_part partition(p) compute statistics for columns;
explain select count(key2) from stats_part; -- <== stats are now correct again

alter table stats_part add partition(p=105);
explain select count(key2) from stats_part; -- <== stats are now incorrect

analyze table stats_part partition(p) compute statistics for columns;
explain select count(key2) from stats_part; -- <== stats are still incorrect!


drop table stats_part;
{noformat}

Seems like it's impossible to have correct stats on a table with an empty 
partition.








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