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From: Dennis Lee Bieber <wlfraed@ix.netcom.com>
Subject: Re: How pickle helps in reading huge files?
Date: Wed, 16 Oct 2013 13:32:33 -0400
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Xref: csiph.com comp.lang.python:56887

On Tue, 15 Oct 2013 23:55:26 -0700 (PDT), Harsh Jha
<harshjha2006@gmail.com> declaimed the following:

>I've a huge csv file and I want to read stuff from it again and again. Is it useful to pickle it and keep and then unpickle it whenever I need to use that data? Is it faster that accessing that file simply by opening it again and again? Please explain, why?
>
	As others mention, what is "huge"?

	Does it get updated often? How extensive are updates?

	I suspect I'd use the CSV module to parse it into an SQLite3 database,
then use the database for the repetitive access. NOTE: I've never used
pickle -- but for stuff that is coming in as simple CSV I'd suspect the
parsing (even including the various int()/float() wrapping of numeric
fields) can't be much slower than the object creation/unwrapping used by
pickle; SQLite3 should let you leave the data in numeric formats without
the translation penalty on each use.

-- 
	Wulfraed                 Dennis Lee Bieber         AF6VN
    wlfraed@ix.netcom.com    HTTP://wlfraed.home.netcom.com/