Indexed sequential access method (ISAM) is used widely for processing database operations among different platforms with definite characteristics. The classification of these indexes in the data set processing determines various managing of the records. They can be shown by several indexes of an employee in the one database that sequentially joined based on the provided set of information. Several issues in managing the data set were addressed in terms of storing, processing, and retrieving of data records into the column, this due to the lacking in understanding the ISAM sequential procedure for managing data. Thus, this paper intends to demonstrate the classification of ISAM within the platforms and the working procedure as well as the indexing schema for this method in processing files.