PREFETCH_MODE Query Option (Impala 2.6 or higher only)
Determines whether the prefetching optimization is applied during join query processing.
Type: numeric (0, 1)
or corresponding mnemonic strings (
Default: 1 (equivalent to
Added in: Impala 2.6.0
The default mode is 1, which means that hash table buckets are prefetched during join query processing.