Data set index record preservation

摘要

Portions of index information are pulled from a name directory and an attribute directory to form a new subindex data set that is stored as a separate file from the name directory and the attribute directory. The name directory and the attribute directory each being associated with partitioned data set extended (PDSE) data sets stored sequentially in members. Pursuant to an update to the PDSE data sets, a selected portion of an index record of the dataset is stored as a record in the new subindex data set and the storing includes acting on an integrated catalog facility catalog to perform operations relating to allowacation and maintenance of the new subindex data set. An oldest existing record is replaced with a recent version if a determination is made that adding the recent version exceeds a predetermined number of versions. A component of the new subindex data set is recoverable.

主权项

1. A method for preserving data set information in a computing storage environment by a processor device, comprising:
pulling portions of index information from a basic catalog structure (BCS) of an integrated catalog facility (ICF) catalog, the BCS pointing to multiple virtual storage access method (VSAM) volume data sets (VVDS) including a volume table of contents (VTOC) and including a name directory and an attribute directory to form a new subindex data set that is stored as a separate file from the name directory and the attribute directory, the name directory and the attribute directory each being associated with partitioned data set extended (PDSE) data sets stored sequentially in members, and the new subindex data set being associated with the PDSE data sets via a catalog entry; pursuant to an update to the PDSE data sets, storing at least one portion of selected portions of an index record of the dataset as a record in the new subindex data set, wherein the step of storing at least one portion includes acting on the ICF catalog to perform operations relating to allocation and maintenance of the new subindex data set; replacing an oldest existing record with a most recent version if a determination is made that adding the most recent version exceeds a predetermined number of versions, wherein at least one component of the new subindex data set is recoverable into the index record in an event of an error detected within the index record; including referring to the new subindex data set to determine a historical change of an index comprising at least the index record to discover the source of an index corruption, in an event the index is corrupted; and including referring to extent location and size field data in the new subindex data set to determine the historical change of the index comprising at least the index record from reviewing each version of the predetermined number of versions to discover the source of an index corruption.