[jira] [Created] (HIVE-6997) Semantic Exception for string comparison filter

["Johndee Burks (JIRA)" <ji...@apache.org>]

Johndee Burks created HIVE-6997:
-----------------------------------

             Summary: Semantic Exception for string comparison filter
                 Key: HIVE-6997
                 URL: https://issues.apache.org/jira/browse/HIVE-6997
             Project: Hive
          Issue Type: New Feature
            Reporter: Johndee Burks
            Priority: Minor


-- Consider that you have the following dataset: 

one,1
two,2
three,three

-- The DDL is the following: 

create table j1 (a string, b string) row format delimited fields terminated by ',';

-- If you do a filter on column b like this: 

select * from j1 where b!=1;

-- I would expect to see the data from row 2 and 3. However you only see row 2. If you make the following change to the query you get the correct results: 

select * from j1 where b!='1';

-- Looking at an explain of both queries it appears that in the query without the quotes the 1 is being changed to 1.0 and then being compared to the string three incorrectly typed so the result is filtered out. I think that this should be improved with a Semantic exception when type of the column is string and the value being passed in the filter is not in quotes. 

== Without Quotes

STAGE PLANS:
  Stage: Stage-1
    Map Reduce
      Alias -> Map Operator Tree:
        j1
          TableScan
            alias: j1
            Filter Operator
              predicate:
                  expr: (b <> 1.0)
                  type: boolean
              Select Operator
                expressions:
                      expr: a
                      type: string
                      expr: b
                      type: string
                outputColumnNames: _col0, _col1
                File Output Operator
                  compressed: false
                  GlobalTableId: 0
                  table:
                      input format: org.apache.hadoop.mapred.TextInputFormat
                      output format: org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat

== With Quotes

STAGE PLANS:
  Stage: Stage-1
    Map Reduce
      Alias -> Map Operator Tree:
        j1
          TableScan
            alias: j1
            Filter Operator
              predicate:
                  expr: (b <> '1')
                  type: boolean
              Select Operator
                expressions:
                      expr: a
                      type: string
                      expr: b
                      type: string
                outputColumnNames: _col0, _col1
                File Output Operator
                  compressed: false
                  GlobalTableId: 0
                  table:
                      input format: org.apache.hadoop.mapred.TextInputFormat
                      output format: org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat





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