This one is an easy question. I am looking for the "idiomatic" way to do it. I have two large data frames. I want to "merge" them. What is the idiomatic way to say "match the rows from dataframe 1 to the rows in dataframe2 which have the following fields the same: Identifier, Year and Quarter? (These three fields form something like a composite primary key in SQL). Then tell me which rows you could not find a match for.... etc. -- Vivek Satsangi Student, Rochester, NY USA
(Newbie) Merging two data frames
2 messages · Vivek Satsangi, Marc Schwartz (via MN)
On Wed, 2006-02-01 at 17:10 -0500, Vivek Satsangi wrote:
This one is an easy question. I am looking for the "idiomatic" way to do it. I have two large data frames. I want to "merge" them. What is the idiomatic way to say "match the rows from dataframe 1 to the rows in dataframe2 which have the following fields the same: Identifier, Year and Quarter? (These three fields form something like a composite primary key in SQL). Then tell me which rows you could not find a match for.... etc.
You answered your own question... :-) See ?merge which will perform SQL-like joins. HTH, Marc Schwartz