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Date: Mon, 22 Dec 2008 10:45:21 -0800 (PST)
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Message-ID: <647fbf98-e633-4d27-b4cb-e510cf19c0be@q18g2000vbn.googlegroups.com>
Subject: R dataframe as in-memory database
From: braver
To: “Kdb+ Personal Developers”
X-Google-Approved: charlie@kx.com via web at 2008-12-22 18:56:11
It occurred to me that Q’s in-memory database is in fact similar to an
R dataframe, which – each dataframe – is its own in-memory
database. With R, you can select by logical conjunctions:
z[z$person_id==i && in_range(z$time,start,finish),]
What’s other folks impression on R vs Q comparison? Both can do
vector operations as well. With 64-bit R, which is finally reliably
here, you can read a whole series of tables, an entire database, into
memory as a series of dataframes, and execute fast queries on them by
logical selection.
Cheers,
Alexy