公开(公告)号：CA2427071A1

公开(公告)日：2004-10-28

申请号：CA2427071

申请日：2003-04-28

Applicant: IBM CANADA

Inventor： LINDSAY BRUCE G ,  BHATTACHARJEE BISHWARANJAN ,  PADMANABHAN SRIRAM K ,  MALKEMUS TIMOTHY R ,  HURAS MATTHEW A ,  MCARTHUR CATHERINE S ,  CRANSTON LESLIE A ,  WINER MICHAEL J

IPC: G06F16/22 ,  G06F17/30

Abstract: An information retrieval system and method of operation therefor, wherein a plurality of dimensions for a table are identified, and at least one block in a plurality of blocks in the table is associated with a dimension value for each dimension in the plurali ty of dimensions, where each block comprises a plurality of contiguous storage pages. Additionally, the at least one block can be further associated with an associated cell, wherein t he associated cell has a unique combination of dimension values comprising an associated dimension value for each dimension in the plurality of dimensions. A unique associated bit list for each dimension value for each dimension in the plurality of dimensions has a uniq ue corresponding list entry for each block associated with that dimension value , and a unique associated bit list for each cell has a unique corresponding list entry for each block associated with that cell. These unique associated bit lists facilitate searching, insertion and deletion of records. Each list entry in the unique associated bit lists may also have an associated storage space indicia bit for its associated block for indicating whether the block is likely to be full for further facilitating insertion of records and management of data storage space. Each block may also have a unique associated empty page bitmap for indicating whe n pages in the block are empty and for identifying when the entire block is empty so that t he block may be disassociated from its associated dimension values and associated cell.

公开(公告)号：CA2426606A1

公开(公告)日：2004-10-25

申请号：CA2426606

申请日：2003-04-25

Applicant: IBM CANADA

Inventor： MCARTHUR CATHERINE S ,  HURAS MATTHEW A ,  THORNBOROUGH SHAUN K ,  WINER MICHAEL J ,  HONG QUANHUA CLAIRE ,  ZHENG ROGER L Q ,  MEADOWCROFT LORYSA M

IPC: G06F16/901 ,  G06F17/30 ,  G06F12/02 ,  G06F17/40

Abstract: The present invention is directed to using a memory buffer to facilitate log catchup for online operations. Some designated areas of memory are allocated for one or more buffers for use during online operations (e.g. reorganization, create index, etc.). Concurrent update activities to the target object write informational records into the one or more buffer s. If the buffers become full, the informational records may be written to logs for persistent storage. After online operations finish building all or a suitable portion of the shadow object, l og catchup is performed by first applying activities in the informational records from the buffer an d thereafter applying activities from logs, if necessary. The invention helps solve the drawbacks of log catchup since the buffer contains only the information related to the target shadow object . Also it does not involve physical I/Os, as these records are all in memory.

公开(公告)号：CA2322603A1

公开(公告)日：2002-04-06

申请号：CA2322603

申请日：2000-10-06

Applicant: IBM CANADA

Inventor： GORALWALLA IQBAL A ,  WINER MICHAEL J ,  SHARPE DAVID C ,  HURAS MATTHEW A

IPC: G06F17/30 ,  G06F12/02 ,  G06F9/312

Abstract: An optimization for updatable scrollable cursors in database systems. To ensure that a temporary copy of a data record matches the data record maintained in the database, th e temporary copy is associated with a timestamp included on each page storing the data records o f the database. The timestamp on a page in the database is updated whenever any record stored on the page is updated. The optimization compares the timestamp stored with the temporary record wit h the current timestamp associated with the page on which the data record is stored in the database. If the two timestamps are matching then the temporary record is identical to the databa se table record and there is no need to carry out a comparison of the attribute values of the temporar y record with the record in the database table.

公开(公告)号：CA2422161C

公开(公告)日：2009-10-06

申请号：CA2422161

申请日：2003-03-14

Applicant: IBM CANADA

Inventor： WINER MICHAEL J ,  LAU LEO TAT MAN ,  BERKS ROBERT T ,  ROMANUFA KERILEY K ,  FLASZA MIROSLAW A ,  HURAS MATTHEW A ,  SACHEDINA AAMER

IPC: G06F17/30 ,  G06F7/00

Abstract: The use of a centralized version table allows for efficient object switching . Rather than synchronizing all database agents to recognize a newly created file as containing the most recent version of a given object, database agents requiring access to t he given object need only consult the centralized version table to learn file identity information. That is, the database agents consult the centralized version table to determine which of the files associated with a given object contain the most recent version of the given object. Mechanisms associated with the use of the centralized version table also provide for efficient recovery from a failure that has occurred during an object switchi ng transaction.

公开(公告)号：CA2422176C

公开(公告)日：2009-07-21

申请号：CA2422176

申请日：2003-03-14

Applicant: IBM CANADA

Inventor： ZHENG ROGER L Q ,  MCINNIS DALE M ,  WINER MICHAEL J ,  MCARTHUR CATHERINE S ,  HURAS MATTHEW A ,  GOSS JEFFREY J ,  ROMANUFA KERILEY K

IPC: G06F16/11

Abstract: A method and system for suspending log-based updating of a database in a manner that permits its resumption without restore, to permit efficient alternation between a log-based update mode and a database access mode. Unplayed log records are protected, as re versions of database pages at a time when the log-based update was suspended. This permits log-based updating to resume where it left off. In order to ensure consistent data for access, a roll-back procedure creates consistent data pagers that are us ed for access, and discarded when log-based update resumes.

公开(公告)号：CA2279051C

公开(公告)日：2004-12-28

申请号：CA2279051

申请日：1999-07-29

Applicant: IBM CANADA

Inventor： WINER MICHAEL J ,  ZHENG ROGER LUO Q ,  WONG CATHARINA K ,  MCKNIGHT KATHY A

IPC: G06F17/30 ,  G06F17/60

Abstract: A lock control data structure for an unit of work of an application program. The unit of work has a set of threads of access for opening a set of objects accessible to th e application program. The lock control data structure has a set of object-specific lock models corresponding to the set of objects, and a lock controller for locking each object in the set of objects . Information regarding the lock requirements for each object are stored in the corresponding object- specific lock model. The lock controller locks and unlocks each object in the set of objects based on the information stored in the corresponding object-specific lock model.

公开(公告)号：CA2422176A1

公开(公告)日：2004-09-14

申请号：CA2422176

申请日：2003-03-14

Applicant: IBM CANADA

Inventor： HURAS MATTHEW A ,  MCINNIS DALE M ,  WINER MICHAEL J ,  MCARTHUR CATHERINE S ,  GOSS JEFFREY J ,  ZHENG ROGER L Q ,  ROMANUFA KERILEY K

IPC: G06F16/11 ,  G06F17/30 ,  G06F17/40

Abstract: A method and system for suspending log-based updating of a database in a manner that permits its resumption without restore, to permit efficient alternation between a log-based update mode and a database access mode. Unplayed log records are protected, as re versions of database pages at a time when the log-based update was suspended. This permits log-based updating to resume where it left off. In order to ensure consistent data for access, a roll-back procedure creates consistent data pagers that are used for access, and discarded when log-based update resumes.

公开(公告)号：CA2422161A1

公开(公告)日：2004-09-14

申请号：CA2422161

申请日：2003-03-14

Applicant: IBM CANADA

Inventor： ROMANUFA KERILEY K ,  HURAS MATTHEW A ,  WINER MICHAEL J ,  FLASZA MIROSLAW A ,  BERKS ROBERT T ,  LAU LEO TAT MAN ,  SACHEDINA AAMER

IPC: G06F7/00 ,  G06F17/30

Abstract: The use of a centralized version table allows for efficient object switching. Rather than synchronizing all database agents to recognize a newly created file as containing the most recent version of a given object, database agents requiring access to the given object need only consult the centralized version table to learn file identity information. That is, the database agents consult the centralized version table to determine which of the files associated with a given object contain the most recent version of the given object. Mechanisms associated with the use of the centralized version table also provide for efficient recovery from a failure that has occurred during an object switching transaction.

公开(公告)号：CA2419883A1

公开(公告)日：2004-08-26

申请号：CA2419883

申请日：2003-02-26

Applicant: IBM CANADA

Inventor： OFER EFFI ,  WINER MICHAEL J ,  HURAS MATTHEW A ,  ZHENG ROGER L Q ,  MCINNIS DALE M

IPC: G06F17/30

Abstract: A system and method for selectively processing log files for enhancing performance of table space recovery by processing only those log files required, as well as choosing which log file to process during recovery for both redo and rollback phases of recover y. The system and method skips the processing of log files that do not contain records of interest for the table space being recovered and determines whether a log file contains anything that nee ds to be played, in particular for the recovery of a subsystem in the database, such as a table space. Pre processing of the log files is not done, rather including tablespace ID correlated with log file ID information is collected while the log files are created. The cross-correlated informati on is used during tablespace recovery to selectively determine which of the log files to process. Some log files may be skipped in cases where not all of the database system is being recovered. A sub set of the database can be recovered, such as a tablespace, and which log files to process is determined based on lock intent.

公开(公告)号：CA2383713A1

公开(公告)日：2003-10-26

申请号：CA2383713

申请日：2002-04-26

Applicant: IBM CANADA

Inventor： HURAS MATTHEW A ,  TREMAINE DAVID ,  BERKS ROBERT T ,  FLASZA MIROSLAW A ,  VALENTIN GARY ,  LAU LEO T M ,  MCARTHUR CATHERINE S ,  WINER MICHAEL J

IPC: G06F16/901 ,  G06F17/30 ,  G06F17/60

Abstract: The invention herein provides method and apparatus for managing attribute- tagged index entries contained in an index by assigning or tagging an index entry attribu te indicator to a newly inserted index entry (that is, at the time when a key data value is inserted into the index, the key data value becomes a newly inserted index entry and an attribute indicator i s tagged to the newly inserted index entry). The index entry can be placed anywhere within the index. Once a group of attribute-tagged index entries have been inserted into the index, the attribute identifiers can be switched off instantaneously (that is, the attribute associated with the attribute indicators is disabled). For example, an attribute identifier can be used to defer accessibility of appropriately attribute-tagged index entries until a predetermined time later when the attribute can be disabled and thus allow users to access the attribute-tagged index entries without having to remove the attribute indicators from the index).