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  1. IMPALA
  2. IMPALA-2635

Hang on UNION query between 2 Kudu tables without computing stats

    Details

    • Type: Bug
    • Status: Resolved
    • Priority: Major
    • Resolution: Fixed
    • Affects Version/s: Kudu_Impala
    • Fix Version/s: Kudu_Impala
    • Component/s: Backend
    • Labels:

      Description

      This was all with Kudu_Impala and Kudu 0.5.0 beta.

      I created 2 Kudu tables, one range partitioned and one hash partitioned, like so:

      CREATE TABLE my_first_table (id BIGINT, name STRING) TBLPROPERTIES ('kudu.master_addresses'='host.example.com:7051', 'kudu.key_columns'='id', 'kudu.table_name'='my_first_table', 'storage_handler'='com.cloudera.kudu.hive.KuduStorageHandler');
      
      CREATE TABLE test_table_1 (id BIGINT, name STRING)
      DISTRIBUTE BY HASH(id) INTO 16 BUCKETS
      TBLPROPERTIES ( 'kudu.master_addresses'='host1.example.com:7051', 'kudu.key_columns'='id', 'kudu.table_name'='test_table_1', 'storage_handler'='com.cloudera.kudu.hive.KuduStorageHandler');
      

      Then insert 2 rows:

      INSERT INTO my_first_table (id, name) VALUES (0, 'Foo');
      INSERT INTO test_table_1 (id, name) VALUES (1, 'Blah');
      

      Now when I do a normal COUNT or SELECT * everything is fine:

      > SELECT * FROM my_first_table;
      Query: select * FROM my_first_table
      +----+------+
      | id | name |
      +----+------+
      | 0  | Foo  |
      +----+------+
      Fetched 1 row(s) in 0.30s
      
      > select * from test_table_1;
      Query: select * from test_table_1
      +----+------+
      | id | name |
      +----+------+
      | 1  | Blah |
      +----+------+
      

      However when I attempt to do a UNION it hangs forever:

      > SELECT * from my_first_table UNION SELECT * from test_table_1;
      Query: select * from my_first_table UNION SELECT * from test_table_1
      

      Doing a COMPUTE STATS on each table prevents the hang, but that should not be required.

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            • Assignee:
              caseyc casey
              Reporter:
              mpercy Mike Percy
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              Dates

              • Created:
                Updated:
                Resolved: