cassandra-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From <>
Subject Subcolumn Indexing
Date Tue, 08 Feb 2011 15:27:50 GMT
I had a question on a sentence about the data model and how things are stored and retrieved
that I came across in the O'Reilly book in the Data Model chapter.

"Cassandra does not index subcolumns, so when you load a super column into memory, all of
its columns are loaded as well."

Does this just mean the exhaustive list of the column names not all the values? So if I have
a super column that has a map of keys that only contain two columns max each this shouldn't
really be a performance concern correct? This becomes an issue when you have lots of subcolumns
if I'm reading this correctly? I'm looking at using the super column as a good way to cluster
data, say I was storing home addresses I might use the zipcode as the super column if I cared
mostly about accessing data by logical area for instance. Thanks for the help.



This e-mail may contain information that is confidential, privileged or otherwise protected
from disclosure. If you are not an intended recipient of this e-mail, do not duplicate or
redistribute it by any means. Please delete it and any attachments and notify the sender that
you have received it in error. Unless specifically indicated, this e-mail is not an offer
to buy or sell or a solicitation to buy or sell any securities, investment products or other
financial product or service, an official confirmation of any transaction, or an official
statement of Barclays. Any views or opinions presented are solely those of the author and
do not necessarily represent those of Barclays. This e-mail is subject to terms available
at the following link: By messaging with Barclays you consent
to the foregoing.  Barclays Capital is the investment banking division of Barclays Bank PLC,
a company registered in England (number 1026167) with its registered office at 1 Churchill
Place, London, E14 5HP.  This email may relate to or be sent from other members of the Barclays

View raw message