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Zhuoluo (Clark) Yang commented on HIVE-4561: -------------------------------------------- [~shreepadma] It seems null value will involve a lot of modification, such as ColumnStatsTask or ObjectStore or thrift files. Currently, statistics are looked up by code, I think it make sense to keep Long.Min/Long.Max. And we can apply HIVE-4561.3.patch instead of HIVE-4561.4.patch. > Column stats : LOW_VALUE (or HIGH_VALUE) will always be 0.0000 ,if all the > column values larger than 0.0 (or if all column values smaller than 0.0) > ---------------------------------------------------------------------------------------------------------------------------------------------------- > > Key: HIVE-4561 > URL: https://issues.apache.org/jira/browse/HIVE-4561 > Project: Hive > Issue Type: Bug > Components: Statistics > Affects Versions: 0.12.0 > Reporter: caofangkun > Assignee: Zhuoluo (Clark) Yang > Attachments: HIVE-4561.1.patch, HIVE-4561.2.patch, HIVE-4561.3.patch > > > if all column values larger than 0.0 DOUBLE_LOW_VALUE always will be 0.0 > or if all column values less than 0.0, DOUBLE_HIGH_VALUE will always be > hive (default)> create table src_test (price double); > hive (default)> load data local inpath './test.txt' into table src_test; > hive (default)> select * from src_test; > OK > 1.0 > 2.0 > 3.0 > Time taken: 0.313 seconds, Fetched: 3 row(s) > hive (default)> analyze table src_test compute statistics for columns price; > mysql> select * from TAB_COL_STATS \G; > CS_ID: 16 > DB_NAME: default > TABLE_NAME: src_test > COLUMN_NAME: price > COLUMN_TYPE: double > TBL_ID: 2586 > LONG_LOW_VALUE: 0 > LONG_HIGH_VALUE: 0 > DOUBLE_LOW_VALUE: 0.0000 # Wrong Result ! Expected is 1.0000 > DOUBLE_HIGH_VALUE: 3.0000 > BIG_DECIMAL_LOW_VALUE: NULL > BIG_DECIMAL_HIGH_VALUE: NULL > NUM_NULLS: 0 > NUM_DISTINCTS: 1 > AVG_COL_LEN: 0.0000 > MAX_COL_LEN: 0 > NUM_TRUES: 0 > NUM_FALSES: 0 > LAST_ANALYZED: 1368596151 > 2 rows in set (0.00 sec) -- This message is automatically generated by JIRA. If you think it was sent incorrectly, please contact your JIRA administrators For more information on JIRA, see: http://www.atlassian.com/software/jira