caofangkun created HIVE-4561:
--------------------------------

             Summary: 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
            Priority: Minor


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;
*************************** 1. row ***************************
                 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)

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