What Is Impala's Aggregation Strategy?

1.	What Is Impala's Aggregation Strategy?
Answer» Impala CURRENTLY only supports in-memory hash aggregation. In Impala 2.0 and higher, if the memory requirements for a join or aggregation operation exceed the memory limit for a particular host, Impala uses a TEMPORARY work AREA on disk to HELP the query complete successfully. Impala currently only supports in-memory hash aggregation. In Impala 2.0 and higher, if the memory requirements for a join or aggregation operation exceed the memory limit for a particular host, Impala uses a temporary work area on disk to help the query complete successfully.

Answer»

Impala CURRENTLY only supports in-memory hash aggregation. In Impala 2.0 and higher, if the memory requirements for a join or aggregation operation exceed the memory limit for a particular host, Impala uses a TEMPORARY work AREA on disk to HELP the query complete successfully.

Impala currently only supports in-memory hash aggregation. In Impala 2.0 and higher, if the memory requirements for a join or aggregation operation exceed the memory limit for a particular host, Impala uses a temporary work area on disk to help the query complete successfully.

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