Hi, please try ?merge DF2$mappedColumn <- DF2$name merge(DF1,DF2,all.x=T,sort=F) ----- A R learner. -- View this message in context: http://r.789695.n4.nabble.com/columns-mapping-tp2305213p2305250.html Sent from the R help mailing list archive at Nabble.com.