Timo Walther created FLINK-10448:
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             Summary: VALUES clause is translated into a separate operator per 
value
                 Key: FLINK-10448
                 URL: https://issues.apache.org/jira/browse/FLINK-10448
             Project: Flink
          Issue Type: Bug
          Components: Table API & SQL
            Reporter: Timo Walther


It seems that a SQL VALUES clause uses one operator per value under certain 
conditions which leads to a complicated job graph. Given that we need to 
compile code for every operator in the open method, this looks inefficient to 
me.

For example, the following query creates and unions 6 operators together:
{code}
SELECT *
  FROM (
    VALUES
      (1, 'Bob', CAST(0 AS BIGINT)),
      (22, 'Alice', CAST(0 AS BIGINT)),
      (42, 'Greg', CAST(0 AS BIGINT)),
      (42, 'Greg', CAST(0 AS BIGINT)),
      (42, 'Greg', CAST(0 AS BIGINT)),
      (1, 'Bob', CAST(0 AS BIGINT)))
    AS UserCountTable(user_id, user_name, user_count)
{code}



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