Abstract: A method and system for displaying database record organization characteristics of IMS databases. In one embodiment, the method involves receiving information associated with a plurality of database records from an IMS database (e.g., information associated with ranges of database records). The database information may comprise information concerning database record organization characteristics. A working storage array may be built to consolidate the information associated with the plurality of database records. A plurality of view envelopes may be constructed. The plurality of view envelopes, along with a legend, may be graphically displayed on a display. User input may be received to request “inspection”, “identification”, “inspection/identification”, or “detailed inspection” of a selected view envelope. Various methods may be used to “mark”, “unmark”, and “submit” at least one DBR to the mainframe computer system for reorganization.

Abstract: A method and system for unloading an IMS database. Segments in the segment array are stored in an indexed order or are stored in a relative byte address (RBA) order. In both cases, either an image copy of an IMS database or an actual IMS database processed sequentially may be utilized. For indexed order storage, a lookup table may be created to include a key value and a segment array location. A segment array may be created to store both the root and child segments from the IMS database. For RBA ordered storage, a first segment array may be created to store the root segments from the IMS database in a sequential order. Additionally, a second segment array may be created to store the child segments from the IMS database in a relative byte address (RBA) order.

Abstract: A method and system for graphically displaying space management data of IMS databases. In one embodiment, the method involves receiving a plurality of records from an IMS database. The plurality of records may comprise ranges of free space within the IMS database, and may be processed to generate database information. The database information may comprise information concerning the condition of blocks in the IMS database and space usage information. Calculations of view ratios may be made. A working storage array may be built to consolidate the plurality of records. A plurality of view envelopes may be constructed. The size for each view envelope may be measured in blocks or in bytes. The plurality of view envelopes may be graphically displayed on a display. A legend may also be displayed on the display. User input may be received to request “inspection” or “identification” of a selected view envelope.

Abstract: A method and system for displaying database record organization characteristics of IMS databases. In one embodiment, the method involves receiving information associated with a plurality of database records from an IMS database (e.g., information associated with ranges of database records). The database information may comprise information concerning database record organization characteristics. A working storage array may be built to consolidate the information associated with the plurality of database records. A plurality of view envelopes may be constructed. The plurality of view envelopes, along with a legend, may be graphically displayed on a display. User input may be received to request “inspection”, “identification”, “inspection/identification”, or “detailed inspection” of a selected view envelope.

Abstract: An improved method and system for analyzing a database for determining a recommended reorganization of a database. In one embodiment, the method involves receiving a list of database records to be analyzed. Each analyzed database record which meets certain criteria may be designated as “qualified”. Identifying information for each qualified database record may be added to a detail array. The qualified database record information may be aggregated based on information in the detail array. The process of aggregating the qualified database record information may include constructing additional arrays (e.g., a roll-up array and a results tracking array). A reorganization strategy may be recommended based on the aggregated qualified database record information. The recommended reorganization strategy may be for an amount (e.g., none, full, partial) of reorganization of the database and a method (e.g., off-line, concurrent, on-line) of reorganization of the database.

Abstract: An improved method and system for on-line reorganization of an IMS database while allowing concurrent updates. In one embodiment, the method involves building and dynamically maintaining a map of free blocks in the IMS database. The user then provides a list of candidate database records to be analyzed. The physical characteristics of each database record on the list are then analyzed. Calculations are made to identify fragmented database records and the segments which contain fragmented boundary twin chains. A reorganization recommendation list is created for each database record on the list, including fragmented boundary twin chains. Each fragmented database record on the reorganization recommendation list is then reorganized.

Abstract: A method and system for analyzing the physical characteristics of database records, such as in IMS databases. The information obtained during this analysis may then be used to perform a more efficient reorganization or restructuring of the database. In one embodiment, the method involves tracing the database retrieval process to collect physical location information for each segment of each database record in an IMS database. The database retrieval process for each database record may begin at the root segment of the database record and traverse the child segments of the database record, preferably in hierarchical order, e.g. top to bottom, left to right. The database retrieval process identifies the segment code causing the first reference to a block and the number of segments retrieved from the block before fetching a new block.