Methods for merging files and related systems. A first file comprising a plurality of columns is provided. Each column comprises at least one data field for a row corresponding to a string identification. It is determined whether the string identification corresponding to the row is in a second file. If the string identification is in the second file, data for the row corresponding to the string identification in a first column of the second file is written to the row in the first column of the first file. If the string identification is not in the second file, data for the row in a second column of the first file is copied to the row in the first column of the first file.