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hive.auto.convert.join

• Default Value: false in 0.10.0; true in 0.11.0 and later (HIVE-3297)  
• Added In: 0.10.0

Whether Hive enables the optimization about converting common join into mapjoin based on the input file size.

hive.auto.convert.join.noconditionaltask

• Default Value: true
• Added In: 0.11.0 with HIVE-3784 (default changed to true with HIVE-4146)

Whether Hive enable enables the optimization about converting common join into mapjoin based on the input file size. If this parameter is on, and the sum of size for n-1 of the tables/partitions for an n-way join is smaller than the size specified by hive.auto.convert.join.noconditionaltask.size, the join is directly converted to a mapjoin (there is no conditional task).

hive.auto.convert.join.noconditionaltask.size

• Default Value: 10000000
• Added In: 0.11.0 with HIVE-3784

If hive.auto.convert.join.noconditionaltask is off, this parameter does not take effect. However, if it is on, and the sum of size for n-1 of the tables/partitions for an n-way join is smaller than this size, the join is directly converted to a mapjoin (there is no conditional task). The default is 10MB.

hive.auto.convert.join.use.nonstaged

• Default Value: true
• Added In: 0.13.0 with HIVE-6144

For conditional joins, if input stream from a small alias can be directly applied to the join operator without filtering or projection, the alias need not be pre-staged in the distributed cache via a mapred local task. Currently, this is not working with vectorization or Tez execution engine.

hive.script.auto.progress

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