What statement are you issuing ? What have you tried ? Cheers
----------------- Aaron Morton Freelance Cassandra Consultant New Zealand @aaronmorton http://www.thelastpickle.com On 8/03/2013, at 5:49 AM, Adam Venturella <aventure...@gmail.com> wrote: > TL;DR: > Is it possible to use WHERE IN on wide rows but only have it return the 1st > column of each of the rows in the IN()? > > First, I am aware that WHERE IN (id1, id2, id3...N) is not the most > performant, and should not be used on large sets. > > Assuming there is also little difference from just issuing N SELECTs from the > requesting application. I'm guessing Cassandra may try to perform some > optimization on it's end, parallelizing the requests to the nodes if > applicable? Otherwise probably, generally speaking, it's more or less the > same-ish as issuing multiple SELECTs. > > That said, I need to extract some data, and WHERE IN() is looking like the > best way to do it given that I have the row keys and just need the data. > > I have a few thousand id's and figure the best way to grab that info is in 10 > id blocks so as not to abuse WHERE IN: IN (1...10), IN(11...20). Now maybe > issuing 100's of WHERE IN's is itself being abusive; my ignorance shows > though. Regardless, I still need to get some data out =) > > The next catch is the rows identified by the keys are wide rows (time > series). Assuming each row is a minimum of 100 columns wide issuing the WHERE > IN seems to pull back all of the columns for each row key specified, as > expected. > > So my question. Is it possible to use WHERE IN on wide rows but only have it > return the 1st column of each of the rows in the IN()? > > I can also just issue SELECTs per row key as well, but I thought I would ask > to see if there was something I was missing using WHERE IN.
