Hi Anuja. Cassandra saves records on disk sorted by the clustering column. In this case you haven't selected any but it looks like is picking birth_year as the clustering column. I don't know which is the clustering column selection algorithm though (maybe alphabetically by name?).
Regards Carlos Alonso | Software Engineer | @calonso <https://twitter.com/calonso> On 12 January 2016 at 07:30, anuja jain <anujaja...@gmail.com> wrote: > 1 more question, what does it mean by "cassandra inherently sorts data"? > For eg: > I have a table with schema > > CREATE TABLE users ( > > ... user_name varchar PRIMARY KEY, > > ... password varchar, > > ... gender varchar, > > ... session_token varchar, > > ... state varchar, > > ... birth_year bigint > > ... ); > > I inserted data in random order but I on firing select statement I get > data sorted by birth_year.. So why does this happen? > > cqlsh:learning> select * from users; > > > > user_name | birth_year | gender | password | session_token | state > > -----------+------------+--------+----------+---------------+--------- > > John | 1979 | M | qwer | abc | JK > > Dharini | 1980 | F | Xyz | abc | Gujarat > > Keval | 1990 | M | DDD | abc | WB > > On Tue, Jan 12, 2016 at 12:52 PM, anuja jain <anujaja...@gmail.com> wrote: > >> What is the alternative if my cassandra version is prior to 3.0 >> (specifically) 2.1) and which is already in production.? >> >> Also as per the docs given at >> >> >> https://docs.datastax.com/en/datastax_enterprise/4.6/datastax_enterprise/srch/srchCapazty.html >> what does it mean by we need to do capacity planning if we need to >> search using SOLR. What is other alternative when we do not know the size >> of the data ? >> >> Thanks, >> >> Anuja >> >> >> >> On Fri, Jan 8, 2016 at 12:15 AM, Tyler Hobbs <ty...@datastax.com> wrote: >> >>> >>> On Thu, Jan 7, 2016 at 6:45 AM, anuja jain <anujaja...@gmail.com> wrote: >>> >>>> My question is, what is the alternative if we need to order by col3 or >>>> col4 in my above example without including col2 in order by clause. >>>> >>> >>> The server-side alternative is to create a second table (or a >>> materialized view, if you're using 3.0+) that uses a different clustering >>> order. Cassandra purposefully only supports simple and efficient queries >>> that can be handled quickly (with a few exceptions), and arbitrary ordering >>> is not part of that, especially if you consider complications like paging. >>> >>> >>> -- >>> Tyler Hobbs >>> DataStax <http://datastax.com/> >>> >> >> >
