Basic Sequential Access Method
BSAM arranges records sequentially in the order in which they are
entered. A data set that has this organization is a sequential data
set. The user organizes records with other records into blocks. This
is basic access. You can use BSAM with the following data types:
- basic format sequential data sets (before z/OS 1.7 these were known as sequential data sets or more accurately as non-extended-format sequential data sets)
- large format sequential data sets
- extended-format data sets
- z/OS UNIX files
Extended-format
data sets have an internal storage format that is different from data sets that are not extended
format. The internal storage format for extended-format data sets provides more usability
characteristics, and can have better performance if the data set is striped. You can choose for an
extended-format data set to be any combination of:
- striped
- encrypted
- compressed format
- or none of those.