I have two TSV (tab separated value) files -- file_A.txt and file_B.txtfile_A.txt contains two columns -- A_ID, A_Namefile_B.txt contains 4 columns -- B_ID1, B_Name1, B_ID2, B_Name2Need to go through each A_ID, if it matches B_ID1 or B_ID2, replace B_Name1 or B_Name2 with A_Name accordingly.I am looking for a way to do it efficiently since file_B is few hundred MB.Any suggestion?
String substitution in large file
scripting