Topic summary
Key-sequenced data set
Extracted from the Wikipedia article Virtual Storage Access Method.
Indexed organization
A key-sequenced data set (KSDS) is a type of data set supported by VSAM. Each record in a KSDS data file is embedded with a unique key. A KSDS consists of two parts, the data component and a separate index file known as the index component which allows the system to physically locate the record in the data file by its key value. Together, the data and index components are called a cluster.