How to join data frames in R (inner, outer, left, right)?

Posted by Dan Goldstein on Stack Overflow See other posts from Stack Overflow or by Dan Goldstein
Published on 2009-08-19T13:18:11Z Indexed on 2010/05/03 15:38 UTC
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r

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join

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inner-join

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outer-join

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sql

Given two data frames

df1 = data.frame(CustomerId=c(1:6),Product=c(rep("Toaster",3),rep("Radio",3)))
df2 = data.frame(CustomerId=c(2,4,6),State=c(rep("Alabama",2),rep("Ohio",1)))

> df1
  CustomerId Product
           1 Toaster
           2 Toaster
           3 Toaster
           4   Radio
           5   Radio
           6   Radio

> df2
  CustomerId   State
           2 Alabama
           4 Alabama
           6    Ohio

How can I do database style, i.e., sql style, joins? That is, how do I get:

An inner join of df1 and df1
An outer join of df1 and df2
A left outer join of df1 and df2
A right outer join of df1 and df2

P.S. IKT-JARQ (I Know This - Just Adding R Questions)

Extra credit:

How can I do a sql style select statement?

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Developer IT

How to join data frames in R (inner, outer, left, right)? - Developer IT

How to join data frames in R (inner, outer, left, right)?

r

join

inner-join

outer-join

sql

Related posts about r

Related posts about join

Improving Partitioned Table Join Performance

MS SQL 2008, join or no join?

SQL Server 2008, join or no join?

Simple join gives unnecessary rows,How to get join properly with only matches in both tables

Mulitple full joins in Postgres is slow

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