Database Versioning Overview
{"Image DocumentName": "Database Versioning Overview", "Image ImageDescription": "IMS 12 Overview. Database Versioning Overview. Database Versioning supports the following database types. DEDB, HDAM, HIDAM, PHDAM, PHIDAM. Can be used in conjunction with the database alter functions to keep track of different versions of the structure of a database. only supports the following database structure changes. For all supported database types. Increasing the length of a fixed-length segment. Adding a new field to space at the end of a fixed-length segment. For Full-Function and HALDB database types. Adding new field(s) that remap existing field(s) and space at the end of a fixed-length segment. Variable-length segments are not supported. Database versioning can be used for the following types of databases: \u2022 DEDB. \u2022 HDAM. \u2022 HIDAM. \u2022 PHDAM. \u2022 PHIDAM. IMS database versioning supports databases that have logical relationships and databases that have secondary indexes. The database versioning function: Can be used in conjunction with the database alter function to keep track of different versions of the structure of a database. Supports the following structural changes to all supported database types: Increasing the length of a segment. Adding a new field at the end of a segment. Supports the following structural changes to FF and HALDB database types. Adding a new field to a segment that remaps / overlays existing fields and space at the end of a segment. Database Versioning only supports changes which include increasing the length of the segment and defining new fields. These changes are normally implemented by recoding the DBD source and running the DBD, PSB, and ACBGEN utilities. The customer will then unload/reload the database or utilize the IMS 13 HALDB Alter function followed by performing an Online Change. Changes made to any existing fields, which include changing the starting position or length of the field are not allowed. Copyright IBM Corp", "Image XResolution": "37", "Image YResolution": "37", "Image ResolutionUnit": "Pixels/Centimeter", "Image Software": "SlidePlayer", "Image YCbCrPositioning": "Centered"}