Skip-sequential access is used to retrieve, update, delete, and add records. When skip-sequential is specified as the mode of access, VSAM retrieves selected records, but in ascending sequence of key values. Skip-sequential processing lets you avoid retrieving a data set or records in the following inefficient ways:

• Entire data set sequentially to process a small percentage of the total number of records
• Desired records directly, which would cause the prime index to be searched from the top to the bottom level for each record