query: CREATE TABLE dest1(key INT, value DOUBLE) STORED AS TEXTFILE
query: EXPLAIN
FROM src INSERT OVERWRITE TABLE dest1 SELECT src.key, sum(substr(src.value,5)) GROUP BY src.key LIMIT 5
ABSTRACT SYNTAX TREE:
  (TOK_QUERY (TOK_FROM (TOK_TABREF src)) (TOK_INSERT (TOK_DESTINATION (TOK_TAB dest1)) (TOK_SELECT (TOK_SELEXPR (. (TOK_TABLE_OR_COL src) key)) (TOK_SELEXPR (TOK_FUNCTION sum (TOK_FUNCTION substr (. (TOK_TABLE_OR_COL src) value) 5)))) (TOK_GROUPBY (. (TOK_TABLE_OR_COL src) key)) (TOK_LIMIT 5)))

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

STAGE PLANS:
  Stage: Stage-1
    Map Reduce
      Alias -> Map Operator Tree:
        src 
          TableScan
            alias: src
            Select Operator
              expressions:
                    expr: key
                    type: string
                    expr: value
                    type: string
              outputColumnNames: key, value
              Group By Operator
                aggregations:
                      expr: sum(substr(value, 5))
                keys:
                      expr: key
                      type: string
                mode: hash
                outputColumnNames: _col0, _col1
                Reduce Output Operator
                  key expressions:
                        expr: _col0
                        type: string
                  sort order: +
                  Map-reduce partition columns:
                        expr: _col0
                        type: string
                  tag: -1
                  value expressions:
                        expr: _col1
                        type: double
      Reduce Operator Tree:
        Group By Operator
          aggregations:
                expr: sum(VALUE._col0)
          keys:
                expr: KEY._col0
                type: string
          mode: mergepartial
          outputColumnNames: _col0, _col1
          Select Operator
            expressions:
                  expr: _col0
                  type: string
                  expr: _col1
                  type: double
            outputColumnNames: _col0, _col1
            Limit
              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/1173614638/10002 
            Reduce Output Operator
              sort order: 
              tag: -1
              value expressions:
                    expr: _col0
                    type: string
                    expr: _col1
                    type: double
      Reduce Operator Tree:
        Extract
          Limit
            Select Operator
              expressions:
                    expr: UDFToInteger(_col0)
                    type: int
                    expr: _col1
                    type: double
              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: dest1

  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: dest1


query: FROM src INSERT OVERWRITE TABLE dest1 SELECT src.key, sum(substr(src.value,5)) GROUP BY src.key LIMIT 5
Input: default/src
Output: default/dest1
query: SELECT dest1.* FROM dest1
Input: default/dest1
Output: file:/data/users/athusoo/commits/hive_trunk_ws1/build/ql/tmp/197588214/10000
0	0.0
10	10.0
100	200.0
103	206.0
104	208.0