query: -- union case: both subqueries are map-reduce jobs on same input, followed by filesink

drop table tmptable
query: create table tmptable(key string, value int)
query: explain 
insert overwrite table tmptable
  select unionsrc.key, unionsrc.value FROM (select 'tst1' as key, count(1) as value from src s1
                                        UNION  ALL  
                                            select 'tst2' as key, count(1) as value from src s2) unionsrc
ABSTRACT SYNTAX TREE:
  (TOK_QUERY (TOK_FROM (TOK_SUBQUERY (TOK_UNION (TOK_QUERY (TOK_FROM (TOK_TABREF src s1)) (TOK_INSERT (TOK_DESTINATION (TOK_DIR TOK_TMP_FILE)) (TOK_SELECT (TOK_SELEXPR 'tst1' key) (TOK_SELEXPR (TOK_FUNCTION count 1) value)))) (TOK_QUERY (TOK_FROM (TOK_TABREF src s2)) (TOK_INSERT (TOK_DESTINATION (TOK_DIR TOK_TMP_FILE)) (TOK_SELECT (TOK_SELEXPR 'tst2' key) (TOK_SELEXPR (TOK_FUNCTION count 1) value))))) unionsrc)) (TOK_INSERT (TOK_DESTINATION (TOK_TAB tmptable)) (TOK_SELECT (TOK_SELEXPR (. (TOK_TABLE_OR_COL unionsrc) key)) (TOK_SELEXPR (. (TOK_TABLE_OR_COL unionsrc) value)))))

STAGE DEPENDENCIES:
  Stage-1 is a root stage
  Stage-2 depends on stages: Stage-1, Stage-6
  Stage-5 depends on stages: Stage-2
  Stage-0 depends on stages: Stage-5
  Stage-6 is a root stage
  Stage-2 depends on stages: Stage-1, Stage-6
  Stage-5 depends on stages: Stage-2
  Stage-0 depends on stages: Stage-5

STAGE PLANS:
  Stage: Stage-1
    Map Reduce
      Alias -> Map Operator Tree:
        null-subquery1:unionsrc-subquery1:s1 
          TableScan
            alias: s1
            Select Operator
              Group By Operator
                aggregations:
                      expr: count(1)
                mode: hash
                outputColumnNames: _col0
                Reduce Output Operator
                  sort order: 
                  tag: -1
                  value expressions:
                        expr: _col0
                        type: bigint
      Reduce Operator Tree:
        Group By Operator
          aggregations:
                expr: count(VALUE._col0)
          mode: mergepartial
          outputColumnNames: _col0
          Select Operator
            expressions:
                  expr: 'tst1'
                  type: string
                  expr: _col0
                  type: bigint
            outputColumnNames: _col0, _col1
            File Output Operator
              compressed: false
              GlobalTableId: 0
              table:
                  input format: org.apache.hadoop.mapred.SequenceFileInputFormat
                  output format: org.apache.hadoop.hive.ql.io.HiveSequenceFileOutputFormat

  Stage: Stage-2
    Map Reduce
      Alias -> Map Operator Tree:
        file:/data/users/athusoo/commits/hive_trunk_ws1/build/ql/tmp/793944135/10002 
          Union
            Select Operator
              expressions:
                    expr: _col0
                    type: string
                    expr: _col1
                    type: bigint
              outputColumnNames: _col0, _col1
              Select Operator
                expressions:
                      expr: _col0
                      type: string
                      expr: UDFToInteger(_col1)
                      type: int
                outputColumnNames: _col0, _col1
                File Output Operator
                  compressed: false
                  GlobalTableId: 1
                  table:
                      input format: org.apache.hadoop.mapred.TextInputFormat
                      output format: org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat
                      serde: org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe
                      name: tmptable
        file:/data/users/athusoo/commits/hive_trunk_ws1/build/ql/tmp/793944135/10004 
          Union
            Select Operator
              expressions:
                    expr: _col0
                    type: string
                    expr: _col1
                    type: bigint
              outputColumnNames: _col0, _col1
              Select Operator
                expressions:
                      expr: _col0
                      type: string
                      expr: UDFToInteger(_col1)
                      type: int
                outputColumnNames: _col0, _col1
                File Output Operator
                  compressed: false
                  GlobalTableId: 1
                  table:
                      input format: org.apache.hadoop.mapred.TextInputFormat
                      output format: org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat
                      serde: org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe
                      name: tmptable

  Stage: Stage-5
    Conditional Operator
      list of dependent Tasks:
          Move Operator
            files:
                hdfs directory: true
                destination: file:/data/users/athusoo/commits/hive_trunk_ws1/build/ql/tmp/1820922097/10000
          Map Reduce
            Alias -> Map Operator Tree:
              file:/data/users/athusoo/commits/hive_trunk_ws1/build/ql/tmp/793944135/10003 
                  Reduce Output Operator
                    sort order: 
                    Map-reduce partition columns:
                          expr: rand()
                          type: double
                    tag: -1
                    value expressions:
                          expr: key
                          type: string
                          expr: value
                          type: int
            Reduce Operator Tree:
              Extract
                File Output Operator
                  compressed: false
                  GlobalTableId: 0
                  table:
                      input format: org.apache.hadoop.mapred.TextInputFormat
                      output format: org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat
                      serde: org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe
                      name: tmptable

  Stage: Stage-0
    Move Operator
      tables:
          replace: true
          table:
              input format: org.apache.hadoop.mapred.TextInputFormat
              output format: org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat
              serde: org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe
              name: tmptable

  Stage: Stage-6
    Map Reduce
      Alias -> Map Operator Tree:
        null-subquery2:unionsrc-subquery2:s2 
          TableScan
            alias: s2
            Select Operator
              Group By Operator
                aggregations:
                      expr: count(1)
                mode: hash
                outputColumnNames: _col0
                Reduce Output Operator
                  sort order: 
                  tag: -1
                  value expressions:
                        expr: _col0
                        type: bigint
      Reduce Operator Tree:
        Group By Operator
          aggregations:
                expr: count(VALUE._col0)
          mode: mergepartial
          outputColumnNames: _col0
          Select Operator
            expressions:
                  expr: 'tst2'
                  type: string
                  expr: _col0
                  type: bigint
            outputColumnNames: _col0, _col1
            File Output Operator
              compressed: false
              GlobalTableId: 0
              table:
                  input format: org.apache.hadoop.mapred.SequenceFileInputFormat
                  output format: org.apache.hadoop.hive.ql.io.HiveSequenceFileOutputFormat


query: insert overwrite table tmptable
select unionsrc.key, unionsrc.value FROM (select 'tst1' as key, count(1) as value from src s1
                                        UNION  ALL  
                                          select 'tst2' as key, count(1) as value from src s2) unionsrc
Input: default/src
Output: default/tmptable
query: select * from tmptable x sort by x.key
Input: default/tmptable
Output: file:/data/users/athusoo/commits/hive_trunk_ws1/build/ql/tmp/1401758833/10000
tst1	500
tst2	500
query: drop table tmptable