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From Aditya Narayan <>
Subject Re: Seeking advice on Schema and Caching
Date Tue, 15 Nov 2011 20:11:54 GMT
Any insights on this ?

On Tue, Nov 15, 2011 at 9:40 PM, Quintero <> wrote:

> Aditya Narayan <> wrote:
> >Hi
> >
> >I need to add 'search users' functionality to my application. (The trigger
> >for fetching searched items(like google instant search) is made when 3
> >letters have been typed in).
> >
> >For this, I make a CF with String type keys. Each such key is made of
> first
> >3 letters of a user's name.
> >
> >Thus all names starting with 'Mar-' are stored in single row (with
> >key="Mar").
> >The column names are framed as remaining letters of the names. Thus, a
> name
> >'Marcos' will be stored within rowkey "Mar" & col name "cos". The id will
> >be stored as column value. Since there could be many users with same name.
> >Thus I would have multple userIds(of users named "Marcos") to be stored
> >inside columnname "cos" under key "Mar". Thus,
> >
> >1. Supercolumn seems to be a better fit for my use case(so that ids of
> >users with same name may fit as sub-columns inside a super-column) but
> >since supercolumns are not encouraged thus I want to use an alternative
> >schema for this usecase if possible. Could you suggest some ideas on this
> ?
> >
> >2. Another thing, I would like to row cache this CF so that when the user
> >types in the next character & the query is made consequently, then this
> row
> >be retrieved from the cache without touching DB. It is expected while
> >searching for a single username, the query(as a part of making
> >instantaneous suggestions) will be made at least 2-3 times. One may also
> >suggest to fetch all the columns starting with queried string to be
> >retrieved & then filter out at application level but what about just
> >fecthing the exact no of columns(ids/names of users) I need to show to the
> >user. Thus instead of keeping all the hundreds of cols in the application
> >layer what about keeping it within the DB cache.!?
> >The space alloted for the cache will be very small so that row remains in
> >cache for a very short time(enough to serve only for the time duration
> >while user is making a single search!?) ?

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