Try, unique(dataset[,1:a]), where a is the number of columns that you have. 1:a would apply the unique to all columns. ----- Lanna Jin lannajin at gmail.com 510-898-8525 -- View this message in context: http://r.789695.n4.nabble.com/Delete-rows-with-duplicate-field-tp2123939p2123976.html Sent from the R help mailing list archive at Nabble.com.