[R] R is not for Relational

[R.E. Darnell]

Russel Senior writes:
>One useful thing that subset() doesn't appear to do is joins.  That is
>frequently what select statements are used for in SQL.  There are
>three S-plus functions (at least, as documented in MASS 2ed) called
>merge, by and aggregate.  The merge() function joins data frames, but
>is not implemented in R that I am aware of, at least as of 0.64.0.

I use match to merge data sets.

B$V2<-A$V2[match(B$V1,A$V1)]

is similar to 
SELECT V1 V2 
     FROM A B
     WHERE A.V1=B.V1

i'nit?

Ross Darnell
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