Bmc Software, Inc.

Christopher Youngs Blaicher

Kerry Charles Tenberg

Randol Keith Bright

Mary D Black, Legal Representative

Donald W Black

A time-efficient means for identifying and processing cascading deletes due to referential constraint violations includes: logging, to an error file, all primary key ('PK') errors detected during table load operations; building a foreign key ('FK') index for each child table; recursively probing each relevant FK index to identify all loaded rows that violate a referential constraint due to a PK error; logging all identified FK errors to the error file; and using the (preferably sorted) error file contents to identify, mark and physically delete table rows that violate a referential constraint. The described cascade delete processing methods make only a single pass through the table data, using ordinary computer files to track and organize rows identified for deletion. Use of error files rather than tablescans (multiple passes through the loaded table data) can provide a significant reduction in table load times, especially for large or intricately &#x201c;related&#x201d; tables.

Cascade delete processing

A database reorganization technique uses multiple-coordinated read, sort and write tasks to substantially reduce the overall time to reorganize a database object. Coordination between the different functional tasks (e.g., read, sort and write tasks) is facilitated through the logical partitioning of the key values associated with the object to be reorganized. Object key values are determined by interrogating the object's associated database prior to initiating reorganization processing.

Database reorganization technique

Constraint processing for a relational database generates primary (e.g., based on primary key values) and constraint index records (e.g., based on foreign key values) during table load operations that are then sorted in a manner that rapidly and unambiguously identifies rows that fail the specified constraint test. Rows so identified may be deleted to maintain the constraint (e.g., referential) integrity of a child table. In one case, child table row data may be processed in constraint key order, eliminating the need first load the child table with row data and then delete those rows that subsequently fail the integrity test.

Constraint processing

Techniques for sorting data include (1) obtaining records containing variable length key fields, (2) expanding the variable length key fields into fixed length key fields in a temporary structure, (3) sorting the temporary structure based on the fixed length key fields, and (4) reorganizing the data containing the variable length key fields in accordance with the sorted temporary structure. Reorganized data can replace the original data or be saved to temporary storage where it can later be merged with other reorganized data. Temporary storage of reorganized data does not incorporate the expanded fixed length key information used in the temporary structure.

Reorganizing database objects using variable length keys

A method and system for inputing data to a sort utility from a user program. In one embodiment, first parameters may facilitate optimization for both programs, by either the user program or the sort utility. The sort utility may process the first parameters to optimize sorting by: returning second parameters to the user program; and supporting a multi-record interface between the two programs. The sort utility may process the data records into the multi-record interface by constructing reformatted data records and inserting the reformatted data records into the multi-record interface, or by utilizing an exit routine to construct and insert the reformatted data records into the multi-record interface. The sort utility may sort the data records (e.g., by directly processing them), optimizing memory usage by the sort utility and/or the user program. The processing and sorting actions of the sort utility program may be coordinated and overlapped.

Growing community of inventors

Austin, TX, United States of America

Christopher Youngs Blaicher