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US6026412A Expired / Lapsed US ⏱️ 0.0 years remaining

Interaction between application of a log and maintenance of a table that maps record identifiers during online reorganization of a database

Assignee: International Business Machines Corp
•
Filing: 1997-06-30
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Granted: 2000-02-15
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Expires: 2017-06-30
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Abstract

Abstract The present invention includes reorganization of a Database Management System (DBMS). The reorganization of the present invention is implemented by recording a first current Relative Byte Address (RBA). Then, data is copied from the old area in the table space to a new area in the table space in reorganized form. In the present invention, throughout most of reorganization a user maintains access to the DBMS's normal facilities to read and write to the old area. The DBMS uses its normal facilities to record writing, which occurs during reorganization, in a log. The reorganization in accordance with the present invention reads the log (that has been written to during reorganization) and processes the log to the new area to bring the new area up to date. This process is performed with the use of a RID mapping table. Finally, at the end of reorganization, the user's access is switched from the old area to the new area.

Inventors

  • 👤 Gary Howard Sockut
  • 👤 Thomas Abel Beavin

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 09:14
CPC Classifications
G; G06; G06F; G06F16/00; G06F16/20; G06F16/22; G06F16/2282; Y; Y10; Y10S; Y10S707/00; Y10S707/99951; Y10S707/99952; Y10S707/99953

Claims Analysis

Total Claims: 56
Claim 1
Independent Claim 151 words
A method for performing reorganization in a database management system (DBMS), comprising the steps of: reorganizing a plurality of data records which originally reside in an old area of a table space, wherein each of said data records has an old record identifier (RID), while read/write access to said old area is retained; directing said reorganized data records to a new area in said table space, wherein each of said data records in said new area has a new RID, while read/write access to said old area is retained; maintaining a mapping table that maps between said old RID and said new RID; translating a log entry RID for a log entry to said new RID using said mapping table, wherein said log entry RID is said old RID; and applying said translated log entry with said new RID to said data records in said new area in said table space.
Claim 2
Independent Claim 151 words
A method for performing reorganization in a database management system (DBMS), comprising the steps of: reorganizing a plurality of data records which originally reside in an old area of a table space, wherein each of said data records has an old record identifier (RID), while read/write access to said old area is retained; directing said reorganized data records to a new area in said table space, wherein each of said data records in said new area has a new RID, while read/write access to said old area is retained; maintaining a mapping table that maps between said old RID and said new RID; translating a log entry RID for a log entry to said new RID using said mapping table, wherein said log entry RID is said old RID; and applying said translated log entry with said new RID to said data records in said new area in said table space.
Claim 3
Dependent Claim 26 words
The method according to claim 1, further comprising the step of copying at least a subset of a log prior to said translating and applying steps.
Claim 4
Dependent Claim 53 words
The method according to claim 1, wherein said reorganizing and directing steps further comprise the steps of: unloading said data records from said old area; reorganizing said data records; reloading said data records in said new area; and inserting an entry containing said old RID and said new RID into said mapping table.
Claim 5
Dependent Claim 27 words
The method according to claim 3, wherein said step of reorganizing said data records further comprises the step of sorting said data records by clustering key values.
Claim 6
Dependent Claim 37 words
The method according to claim 1, wherein said log entry comprises a plurality of log entries, and said method further comprises the step of sorting said log entries by said old RIDs prior to said translating step.
Claim 7
Dependent Claim 19 words
The method according to claim 5, wherein said translating step further comprises the step of calculating a new RID.
Claim 8
Dependent Claim 37 words
The method according to claim 1, wherein said log entry comprises a plurality of log entries, and said method further comprises the step of sorting said log entries by said new RIDs prior to said applying step.
Claim 9
Dependent Claim 35 words
The method according to claim 1, wherein said step of maintaining a mapping table further comprises the steps of updating said mapping table for each log entry to reflect a state of said data records.
Claim 10
Dependent Claim 35 words
The method according to claim 1, wherein said step of maintaining a mapping table further comprises the step of updating said mapping table for each log entry to reflect a type of said log entry.
Claim 11
Dependent Claim 34 words
The method according to claim 1, wherein said step of applying said log entry further comprises the step of updating a column containing an indicator of log position for each of said data records.
Claim 12
Dependent Claim 23 words
The method according to claim 10, wherein said indicator of log position further comprises a log sequence number or a relative byte address.
Claim 13
Independent Claim 162 words
A method for reorganizing a database, comprising the steps of: recording a first log sequence number (LSN) from a log as a first variable, while read/write access to an old area of a table space is retained; performing reorganization of a plurality of data records, each having an old record identifier (RID) from said old area of said table space, such that a reorganized version of said data records, each having a new RID in a new area of said table space, is directed to said new area while read/write access to said old area is retained; recording a second LSN from said log as a second variable; and applying each log entry between said first variable and said second variable to said reorganized version of said data record identified by said new RID in said new area by using a RID mapping table to translate said old RID to said new RID, while read/write access to said old area is retained.
Claim 14
Independent Claim 162 words
A method for reorganizing a database, comprising the steps of: recording a first log sequence number (LSN) from a log as a first variable, while read/write access to an old area of a table space is retained; performing reorganization of a plurality of data records, each having an old record identifier (RID) from said old area of said table space, such that a reorganized version of said data records, each having a new RID in a new area of said table space, is directed to said new area while read/write access to said old area is retained; recording a second LSN from said log as a second variable; and applying each log entry between said first variable and said second variable to said reorganized version of said data record identified by said new RID in said new area by using a RID mapping table to translate said old RID to said new RID, while read/write access to said old area is retained.
Claim 15
Dependent Claim 66 words
The method according to claim 12, further comprising the steps of: recording a third LSN from said log as a third variable; applying said log entries between said second and third LSN variables to said reorganized version of said data records identified by said new RIDs, by using said RID mapping table to translate said old RIDs to said new RIDs, while read-only access is retained.
Claim 16
Dependent Claim 60 words
The method of claim 13, further comprising the steps, after recording said third variable of: comparing, on a next iteration, a difference between said third variable and said second variable with a first predetermined value; if said comparison is greater than or equal to a second predetermined value, then implementing an action to allow a log application to catch up.
Claim 17
Dependent Claim 28 words
The method of claim 14, wherein said step of allowing said log application to catch up further comprises the step of quiescing write access to said old area.
Claim 18
Dependent Claim 26 words
The method of claim 14, wherein said step of allowing said log application to catch up further comprises the step of increasing scheduling priority of reorganization.
Claim 19
Dependent Claim 28 words
The method of claim 14, wherein said step of allowing said log application to catch up further comprises the step of asking an operator to choose an action.
Claim 20
Dependent Claim 38 words
The method of claim 14, further comprising the step of, if said comparison is not above said predetermined value, recording a new LSN variable and continuing with a next iteration from previous LSN variable to current LSN variable.
Claim 21
Dependent Claim 21 words
The method of claim 14, wherein said first predetermined value comprises a difference between said second variable and said first variable.
Claim 22
Dependent Claim 12 words
The method of claim 19, wherein said second predetermined value is zero.
Claim 23
Dependent Claim 31 words
The method according to claim 14, further comprising the step of iterati vely repeating said steps until all log values have been applied to said reorganized version of said data records.
Claim 24
Dependent Claim 40 words
The method of claim 21, further comprising the steps of: quiescing all access of said old data area; converting access from said old area to said new area; and starting read/write access to said table space containing said new area.
Claim 25
Dependent Claim 30 words
The method of claim 22, further comprising the step, after the step of starting read/write access to said new area, of erasing said old area and said RID mapping table.
Claim 26
Dependent Claim 19 words
The method of claim 22, further comprising the step of creating a backup copy of said new data area.
Claim 27
Dependent Claim 51 words
The method of claim 13, further comprising the steps, after recording said third variable of: comparing, on a next iteration, a difference between said third variable and said second variable with a first predetermined value; if said comparison is greater than or equal to a second predetermined value, then terminating reorganization.
Claim 28
Dependent Claim 40 words
The method of claim 13, further comprising the steps of: quiescing all access of said old data area; converting access from said old area to said new area; and starting read/write access to said table space containing said new area.
Claim 29
Dependent Claim 30 words
The method of claim 26, further comprising the step, after the step of starting read/write access to said new area, of erasing said old area and said RID mapping table.
Claim 30
Dependent Claim 19 words
The method of claim 26, further comprising the step of creating a backup copying of said new data area.
Claim 31
Dependent Claim 183 words
A computer program product, comprising: a computer usable medium having computer readable program code means embodied in said medium for causing a database management system (DBMS) to be reorganized, the computer readable program code comprising, computer readable program code means for reorganizing a plurality of data records which originally reside in an old area of a table space, wherein each of said data records has an old record identifier (RID); computer readable program code means for directing said reorganized data records to a new area in said table space, wherein each of said data records in said new area has a new RID; computer readable program code means for maintaining a mapping table that maps between said old RID and said new RID; computer readable program code means for translating a log entry RID for a log entry to said new RID using said mapping table, wherein said log entry RID is said old RID; and computer readable program code means for applying said translated log entry with said new RID to said data records in said new area in said table space.
Claim 32
Dependent Claim 183 words
A computer program product, comprising: a computer usable medium having computer readable program code means embodied in said medium for causing a database management system (DBMS) to be reorganized, the computer readable program code comprising, computer readable program code means for reorganizing a plurality of data records which originally reside in an old area of a table space, wherein each of said data records has an old record identifier (RID); computer readable program code means for directing said reorganized data records to a new area in said table space, wherein each of said data records in said new area has a new RID; computer readable program code means for maintaining a mapping table that maps between said old RID and said new RID; computer readable program code means for translating a log entry RID for a log entry to said new RID using said mapping table, wherein said log entry RID is said old RID; and computer readable program code means for applying said translated log entry with said new RID to said data records in said new area in said table space.
Claim 33
Dependent Claim 24 words
The computer program product according to claim 29, further comprising computer readable program code means for copying at least a subset of a log.
Claim 34
Dependent Claim 81 words
The computer program product according to claim 29, wherein said computer readable program code means for reorganizing and directing further comprises: computer readable program code means for unloading said data records from said old area; computer readable program code means for reorganizing said data records; computer readable program code means for reloading said data records in said new area; and computer readable program code means for inserting an entry containing said old RID and said new RID into said mapping table.
Claim 35
Dependent Claim 36 words
The computer program product according to claim 31, wherein said computer readable program code means for reorganizing said data records further comprises computer readable program code means for sorting said data records by clustering key values.
Claim 36
Dependent Claim 39 words
The computer program product according to claim 29, wherein said log entry comprises a plurality of log entries, and said computer program product further comprises computer readable program code means for sorting said log entries by said old RIDs.
Claim 37
Dependent Claim 29 words
The computer program product according to claim 33, wherein said computer readable program code means for translating further comprises computer readable program code means for calculating a new RID.
Claim 38
Dependent Claim 39 words
The computer program product according to claim 29, wherein said log entry comprises a plurality of log entries, and said computer program product further comprises computer readable program code means for sorting said log entries by said new RIDs.
Claim 39
Dependent Claim 44 words
The computer program product according to claim 29, wherein said computer readable program code means for maintaining a mapping table further comprises computer readable program code means for updating said mapping table for each log entry to reflect a state of said data records.
Claim 40
Dependent Claim 44 words
The computer program product according to claim 29, wherein said computer readable program code means for maintaining a mapping table further comprises computer readable program code means for updating said mapping table for each log entry to reflect a type of said log entry.
Claim 41
Dependent Claim 43 words
The computer program product according to claim 29, wherein said computer readable program code means for applying said log entry further comprises computer readable program code means for updating a column containing an indicator of log position for each of said data records.
Claim 42
Dependent Claim 25 words
The computer program product according to claim 38, wherein said indicator of log position further comprises a log sequence number or a relative byte address.
Claim 43
Dependent Claim 180 words
A computer program product, comprising: a computer usable medium having computer readable program code means embodied in said medium for causing a database management system (DBMS) to be reorganized, the computer readable program code comprising, computer readable program code means for recording a first log sequence number (LSN) from a log as a first variable; computer readable program code means for performing reorganization of a plurality of data records, each having an old record identifier (RID) from said old area of said table space, such that a reorganized version of said data records, each having a new RID in a new area of said table space, is directed to said new area; computer readable program code means for recording a second LSN from said log as a second variable; and computer readable program code means for applying each log entry between said first variable and said second variable to said reorganized version of said data record identified by said new RID in said new area by using a RID mapping table to translate said old RID to said new RID.
Claim 44
Dependent Claim 180 words
A computer program product, comprising: a computer usable medium having computer readable program code means embodied in said medium for causing a database management system (DBMS) to be reorganized, the computer readable program code comprising, computer readable program code means for recording a first log sequence number (LSN) from a log as a first variable; computer readable program code means for performing reorganization of a plurality of data records, each having an old record identifier (RID) from said old area of said table space, such that a reorganized version of said data records, each having a new RID in a new area of said table space, is directed to said new area; computer readable program code means for recording a second LSN from said log as a second variable; and computer readable program code means for applying each log entry between said first variable and said second variable to said reorganized version of said data record identified by said new RID in said new area by using a RID mapping table to translate said old RID to said new RID.
Claim 45
Dependent Claim 72 words
The computer program product according to claim 40, further comprising: computer readable program code means for recording a third LSN from said log as a third variable; computer readable program code means for applying said log entries between said second and third LSN variables to said reorganized version of said data records identified by said new RIDs, by using said RID mapping table to translate said old RIDs to said new RIDs.
Claim 46
Dependent Claim 50 words
The computer program product according to claim 41, further comprising: computer readable program code means for comparing a difference between said third variable and said second variable with a first predetermined value; and computer readable program code means for implementing an action to allow a log application to catch up.
Claim 47
Dependent Claim 37 words
The computer program product of claim 42, wherein said computer readable program code means for allowing said log application to catch up further comprises computer readable program code means for quiescing write access to said old area.
Claim 48
Dependent Claim 35 words
The computer program product of claim 42, wherein said computer readable program code means for allowing said log application to catch up further comprises computer readable program code means for increasing scheduling priority of reorganization.
Claim 49
Dependent Claim 37 words
The computer program product of claim 42, wherein said computer readable program code means for allowing said log application to catch up further comprises computer readable program code means for asking an operator to choose an action.
Claim 50
Dependent Claim 40 words
The computer program product of claim 42, further comprising: computer readable program code means for recording a new LSN variable; and computer readable program code means for continuing with a next iteration from previous LSN variable to current LSN variable.
Claim 51
Dependent Claim 23 words
The computer program product of claim 42, wherein said first predetermined value comprises a difference between said second variable and said first variable.
Claim 52
Dependent Claim 14 words
The computer program product of claim 47, wherein said second predetermined value is zero.
Claim 53
Dependent Claim 44 words
The computer program product of claim 41, further comprising: computer readable program code means for comparing, on a next iteration, a difference between said third variable and said second variable, with a first predetermined value; and computer readable program code means for terminating reorganization.
Claim 54
Dependent Claim 57 words
The computer program product of claim 41, further comprising: computer readable program code means for quiescing all access of said old data area; computer readable program code means for converting access from said old area to said new area; and computer readable program code means for starting read/write access to said table space containing said new area.
Claim 55
Dependent Claim 24 words
The computer program product of claim 50, further comprising computer readable program code means for erasing said old area and said RID mapping table.
Claim 56
Dependent Claim 24 words
The computer program product of claim 50, further comprising computer readable program code means for creating a backup copying of said new data area.

References Cited (Backward Citations)

US5414834A Cited
US5455945A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2003-02-14 2003-08-16 2004-02-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2007-02-14 2007-08-16 2008-02-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2011-02-14 2011-08-16 2012-02-15 $7700.00 Window Closed / Lapsed

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