quick matching question

Hey,

I'm trying to match patient identifiers from two separate input files, and
then add information from one of the input files to the corresponding output
file. ?I'd greatly appreciate any help!

More specifically,
Input_File_1 has a column header "bcr_patient_barcode"
Input_File_2 has a column header "Barcode" and a column header "Batch"

I want my script to match the appropriate patient identifiers since
"bcr_patient_barcode" and "Barcode" are not in the same order. ?Then I want
to add the information from "Batch" to the corresponding patient.

My (incorrect) code is below:

#batch
tmp <- Input_File_2$Barcode
tmp1 <- Input_File_1$bcr_patient_barcode

for i in tmp
?for item in tmp1
if (tmp == tmp1) {
?curated$batch <- Input_File_2$Batch
}