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From <Jeremy.Truel...@barclayscapital.com>
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.

jt

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