Message-ID: <CAP01uRniUUEaRAizV6nG=DAd7KTyoeDAF_T-fVUYNUVUebJVJA@mail.gmail.com>
Date: 2012-11-23T16:49:43Z
From: Gabor Grothendieck
Subject: read.csv.sql() to select from a large csv file
In-Reply-To: <1353687149.77196.YahooMailNeo@web171701.mail.ir2.yahoo.com>
On Fri, Nov 23, 2012 at 11:12 AM, Juliane Struve
<juliane_struve at yahoo.co.uk> wrote:
> Dear list,
>
> Dear list,
> I am using read.csv.sql() from the sqldf package to read
> individual-based data from a csv file that is too large for R.
> My original file contains a column called ?ID? that
> identifies the individual. I would like to read in data for only
> one individual at a
> time, for example "Bobby".
> read.csv.sql("filename",sql = 'select * from file where ID = ?Bobby?') works fine, but
> Name <- "Bobby"
> read.csv.sql("filename",sql = 'select * from file
> where ID = Name') gives me an error message
> ?Error in sqliteExecStatement(con, statement,
> bind.data) :
> RS-DBI driver: (error in statement: no such column: Name)?
>
> I would like to use a variable in the select statement because I have many individuals in the original csv file, is this possible ? I have no experience with sql, perhaps someone can kindly point out how to do this correctly or offer an alternative solution ?
See Example 5 on the sqldf home page:
https://code.google.com/p/sqldf/#Example_5._Insert_Variables
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Statistics & Software Consulting
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tel: 1-877-GKX-GROUP
email: ggrothendieck at gmail.com