AHA!!!!! haha On Wed, Aug 31, 2011 at 6:17 PM, Dmitriy Ryaboy <[email protected]> wrote:
> They do. You can just flip between left and right outers as needed, right? > > D > > On Wed, Aug 31, 2011 at 6:13 PM, Kevin Burton <[email protected]> wrote: > > > Due to the syntax of left joins, you can't change the order: > > > > alias = JOIN left-alias BY left-alias-column [LEFT|RIGHT|FULL] [OUTER], > > right-alias BY right-alias-column [USING 'replicated' | 'skewed' | > 'merge'] > > [PARTITION BY partitioner] [PARALLEL n]; > > > > …. so I assume the regular join optimizations don't apply here? I > imagine > > this being defined as a 'regular' join … > > > > > > > > > Optimization for regular joins ensures that the last table in the join > is > > > not brought into memory but streamed through instead. Optimization > > reduces > > > the amount of memory used which means you can avoid spilling the data > and > > > also should be able to scale your query to larger data volumes. > > > To take advantage of this optimization, make sure that the table with > the > > > largest number of tuples per key is the last table in your query. In > some > > of > > > our tests we saw 10x performance improvement as the result of this > > > optimization. > > > > > > > > -- > > > > Founder/CEO Spinn3r.com > > > > Location: *San Francisco, CA* > > Skype: *burtonator* > > > > Skype-in: *(415) 871-0687* > > > -- Founder/CEO Spinn3r.com Location: *San Francisco, CA* Skype: *burtonator* Skype-in: *(415) 871-0687*
