High Speed Sequential Retrieval

The architecture of HSSR comprised several key components. The input reader was responsible for accessing the IMS database. The data formatter converted the database records into a sequential format.

The output writer wrote the formatted data to the sequential output dataset. The input reader utilized IMS database access methods to read data from the IMS database. The data formatter handled the conversion of database records into a sequential format suitable for the output dataset.

The output writer wrote the formatted data to a sequential dataset. HSSR used JCL to define the input and output datasets, control parameters, and execution environment. The JCL specified the IMS database to be unloaded, the output dataset characteristics, and any processing options.

The JCL would include statements to allocate the input and output datasets, define the IMS database, and execute the HSSR utility. Example JCL would include statements like //HSSR EXEC PGM=HSSR, and //SYSUT1 DD... HSSR did not expose any APIs.

It was a batch utility designed to be invoked through JCL within the z/OS environment. There were no programmatic interfaces for external applications to interact with HSSR. HSSR is no longer supported; the IMS System Utilities are the recommended replacement.