Hi Yosi, You can have a look at DefaultParallelIteratorRegionSplitter.java code to understand how the api creates splits based on various heuristics like phoenix.query.targetConcurrency and phoenix.query.maxConcurrency . The default value of phoenix.query.targetConcurrency is 32. Try changing the value for targetConcurrency to 31 and I believe you would see 31 parallel scans.
Please note , I haven't tested this . Regards Ravi On Wed, Mar 12, 2014 at 7:14 PM, Yosi Botzer <[email protected]> wrote: > Hi, > > There is something I cannot understand regrading the explain plan of > phoenix. I have a table that has 31 regions all together, however the > explain plan of the query below suggests that there are 62 parallel scans, > > how could it be? > > Yosi > > > 0: jdbc:phoenix:ec2-54-203-158-70.us-west-2.c> explain select campaign_id, > count(*) from fact5 group by campaign_id; > +------------+ > | PLAN | > +------------+ > | CLIENT PARALLEL *62-WAY* FULL SCAN OVER FACT5 | > | SERVER FILTER BY FIRST KEY ONLY | > | SERVER AGGREGATE INTO DISTINCT ROWS BY [CAMPAIGN_ID] | > | CLIENT MERGE SO >
