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Sergey Shelukhin commented on HIVE-19326: ----------------------------------------- [~ashutoshc] [~prasanth_j] looks like a stats issue that may cause problems with metadata only queries. Can you confirm the latter part (ie whether this is important if BASIC_STATS=true but numRows is wrong). > union_fast_stats golden file has incorrect "accurate" stats > ----------------------------------------------------------- > > Key: HIVE-19326 > URL: https://issues.apache.org/jira/browse/HIVE-19326 > Project: Hive > Issue Type: Bug > Reporter: Sergey Shelukhin > Assignee: Ashutosh Chauhan > Priority: Major > > Found when investigating results change after converting tables to MM, turns > out the MM result is correct but the current one is not. > The test ends like so: > {noformat} > desc formatted small_alltypesorc_a; > ANALYZE TABLE small_alltypesorc_a COMPUTE STATISTICS; > desc formatted small_alltypesorc_a; > insert into table small_alltypesorc_a select * from small_alltypesorc1a; > desc formatted small_alltypesorc_a; > {noformat} > The results from the descs in the golden file are: > {noformat} > COLUMN_STATS_ACCURATE {\"BASIC_STATS\":\"true\"} > numFiles 1 > numRows 5 > ... > COLUMN_STATS_ACCURATE {\"BASIC_STATS\":\"true\"} > numFiles 1 > numRows 15 > ... > COLUMN_STATS_ACCURATE {\"BASIC_STATS\":\"true\"} > numFiles 2 > numRows 20 > {noformat} > Note the result change after analyze - the original nomRows is inaccurate, > but BASIC_STATS is set to true. > I am assuming with metadata only optimization this can produce incorrect > results. -- This message was sent by Atlassian JIRA (v7.6.3#76005)