System and method for backing up and restoring groupware documents

• US 5,754,782 A
• Filed: 12/04/1995
• Issued: 05/19/1998
• Est. Priority Date: 12/04/1995
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Masada, Debra Nakanishi
• Primary Examiner(s): Voeltz, Emanuel T.
• Assistant Examiner(s): Nguyen, Cuong H.
• Application Number:
  US08/568,890
• Time in Patent Office: 897 Days
• Field of Search: 395/613, 395/612, 395/492, 395/603, 395/604, 395/614, 395/615, 395/617, 395/616, 395/620, 395/621, 364/963, 364/283.3, 364/222.82, 364/282.4, 364/283.1, 364/283.2, 364/283.4, 364/251.6, 364/225.4, 364/246, 364/281.3, 364/281.6, 364/974.4 , 364/974.6, 364/286.2
• US Class Current: 709/213
• CPC Class Codes: G06F 11/1464 for networked environments

Abstract

A system and method employing logic coupled to a groupware document server and a backup server for enabling back up and restore of a document stored in a document database on the groupware server. The logic is configured with means for restoring an existing document in the groupware document database and also for restoring a document in the database that is marked as being unopenable. The logic is further configured for either restoring a single existing document in the database or a plurality of documents.

Claims

1. In a data processing system including a groupware document server managing a plurality of documents stored in a groupware document database, the groupware document server having groupware server logic, the system further including a backup server coupled to the groupware document server for providing backup services, and main memory coupled to the groupware document server, each document in the plurality of documents containing zero or more data items and having one or more internal identifiers (IDs) that identify the document to the groupware server logic, the database including a database path identifying a storage location of the document, wherein the server logic is configured to allow viewing of documents stored in the database, a method for ensuring data integrity of at least one document of the plurality of documents, the method comprising:

querying the groupware server logic to determine items contained in at least one specified document and internal IDs used to identify the at least one specified document;

building for the at least one specified document, a document data object with a data structure having a plurality of data fields, the plurality of data fields including zero or more item data fields containing information describing corresponding items contained in the at least one specified document, at least one identifier field containing information describing internal IDs used to identify at least one specified document and a database path field representing a database path; and

backing up the groupware document database or restoring the at least one specified document in response to information contained in the plurality of data fields in the document data object.

2. The method of claim 1, wherein backing up includes incrementally backing up of the groupware database by:

identifying documents that have been changed since a previous backup operation;

specifying each document identified during the identifying step by building a document data object for the document;

sending each data object built during the specifying step to the backup server; and

performing a backup operation on the backup server using information contained in the sent data objects for each specified document.

3. The method of claim 2, wherein the identifying step includes the step of identifying one or more documents having accompanying deletion markers that indicate that the one or more documents are marked for deletion from the groupware document database.

4. The method of claim 2, wherein, in the identifying step, a document is identified as changed if it has data that has been modified since the last back up operation.

5. The method of claim 2, wherein, in the identifying step, a document is identified as changed if the document has been added to the groupware document database since the last back up operation.

6. The method of claim 2, wherein a document has been changed if new data has been added to the document since the last backup operation.

7. The method of claim 2, wherein, in the identifying step, a document is identified as changed if it has been marked to be deleted.

8. The method of claim 2, wherein the groupware server manages a plurality of groupware document databases, each having a plurality of documents and the method performs the step of incrementally by backing up each groupware document database of the plurality of groupware document databases substantially simultaneously.

9. The method of claim 3, further comprising notifying the backup server of identified documents having deletion markers, and deleting the identified documents having deletion markers at the backup server.

10. The method of claim 1, the data processing system including means for marking a document as unopenable, wherein restoring the at least one specified document when the document is marked as unopenable includes:

(a) retrieving into the main memory a most recent backup copy of the document marked as being unopenable;

(b) building a document data object for the most recent backup copy;

(c) storing information from the document data object describing the internal IDs of the most recent backup copy into the main memory;

(d) storing the most recent backup copy in the groupware document database;

(e) reading the most recent backup copy from the groupware document database and comparing internal IDs in the most recent backup copy with the internal IDs stored in the main memory; and

,

if the internal IDs do not match;

(f) deleting the document marked as unopenable from the groupware document database; and

(g) replacing the unique document IDs of the most recent backup copy stored in the groupware document database with the internal IDs stored in main memory;

otherwise, repeating steps (a)-(e) until the IDs match.

11. The method of claim 1, wherein the at least one specified document has been selected for viewing and restoring the at least one specified document includes:

building a document data object for the document;

retrieving into main memory a backup copy of the document from the backup server;

using information contained in the document data object to reconstruct the document;

updating the backup copy in main memory with information from the reconstructed document; and

replacing the document with the backup copy in the database.

12. The method of claim 1, wherein restoring includes restoring a plurality of documents belonging to the groupware document database on the groupware server by:

building a plurality of document data objects, wherein each document data object represents an eligible backup copy of a document to be restored, eligibility being determined by comparing a record of a time when the backup copy was created to a predetermined time criterion;

creating a restore list containing each of the document data objects that represent eligible backup copies;

sorting the restore list to minimize potential mounts of media used by the backup server;

obtaining from the backup server a backup copy for each document represented by a document data object in the restore list of the document from the backup server; and

for each obtained backup copy replacing each document in the groupware document database corresponding to a data object in the restore list for which a respective backup copy is obtained.

13. The method of claim 12, wherein if a document represented by a document data object in the restore list is marked as being unopenable then the unopenable document is restored by:

retrieving into the main memory a backup copy of a document marked by the groupware server logic as being unopenable;

building a document data object for the retrieved unopenable document;

storing the information from the document data object describing the internal IDs of the backup copy into the main memory;

storing the backup copy in the document database;

reading the newly stored document from the database to compare its id with the id save in main memory;

conditionally deleting the unopenable document from the database; and

replacing the unique document IDs of the backup copy stored in the document database with the internal IDs stored in main memory.

14. A data processing system for enabling back up and restore of at least one groupware document of a plurality of groupware documents stored in a groupware document database on a groupware document server having groupware server logic, each document containing zero or more data items and having an internal identifier (ID) that is used to identify the document to the groupware server logic and further having a database path identifying a storage location of the document, the server logic being configured to allow viewing of documents stored in the database, the system comprising:

a groupware document server having a plurality of documents stored in a groupware document database;

a backup server coupled through a communications network to the groupware document server;

main memory coupled to the groupware document server; and

logic coupled to main memory and the backup server and to the groupware document server and having machine-executed means for;

querying the groupware server logic to determine what items are contained in at least one specified document and what internal IDs are used to identify the at least one specified document to the groupware server logic;

building a data object for the at least one specified document that includes a data structure having a plurality of data fields, the plurality of data fields including zero or more item data fields containing information describing each item contained in the at least one specified document, at least one identifier field containing information describing internal IDs that are used to identify the particular document to the groupware server logic; and

using the data object to ensure data integrity of the particular document by enabling back up and restore operations that use the information contained in the data fields in the data object.

15. The system of claim 14, wherein the back up operations enabled by the building of the data object include operations to incrementally perform a back up of the groupware database by:

searching through the database to identify the documents that have been changed since the last back up operation;

specifying each document identified during the searching step, and in response to the specifying of a document building the data object;

sending each built data object to the backup server; and

performing a back up operation on the backup server using information contained in the sent data objects for each specified document.

16. The system of claim 15, wherein the means for searching includes means for searching to identify documents having accompanying deletion markers that indicate that the identified document is marked for deletion from the database.

17. The system of claim 15, wherein a document is identified as changed if it has data that has been modified since the last back up operation.

18. The system of claim 15, wherein a document is identified as changed if the document itself has been added since the last back up operation.

19. The system of claim 15, wherein data has been modified if new data has been added to the document since the last back up operation.

20. The system of claim 15, wherein a document is identified as changed if it has been marked to be deleted as a deletion stub.

21. The system of claim 15, wherein the groupware server includes a plurality of document databases each having a plurality of documents and the system performs the incremental back up on each database of the plurality of databases in a substantially simultaneous operation.

22. The system of claim 16, further comprising means for notifying the backup server of identified documents having deletion markers that are to be deleted by the backup server.

23. The system of claim 14, wherein the restore operations enabled by the building of the data object include operations to restore a document in the database that is marked as being unopenable by the groupware server logic by:

retrieving into the main memory a most recent backup copy of a document marked by the groupware server logic as being unopenable;

building the data object for the retrieved unopenable document;

storing the information from the data object describing the internal IDs of the backup copy into the main memory;

storing the backup copy in the document database;

reading the newly stored document from the database to compare its id with the id saved in main memory;

conditionally deleting the unopenable document from the database; and

replacing the unique document IDs of the backup copy stored in the document database with the internal IDs stored in main memory.

24. The system of claim 14, wherein the restore operations enabled by the building of the data object include operations to restore an existing document by:

building the data object for a document selected for a document viewing operation;

retrieving into main memory a backup copy of the selected document from the backup server;

interpreting the information contained in the data object to reconstruct the document;

updating the backup copy in main memory with information from the reconstructed document; and

replacing the selected document with the backup copy in the database.

25. The system of claim 14, wherein the restore operations enabled by the building of the data object include operations for restoring a plurality of existing documents belonging to the groupware document database on the groupware server by:

building a plurality of the data objects, wherein each built data object represents an eligible backup copy of a document to be restored, wherein eligibility is determined by comparing a date and time record of when the backup copy was created to a predetermined date and time criterion;

creating a restore list containing each of the data objects representing eligible backup copies;

sorting the restore list to minimize potential mounts of media used by the backup server;

obtaining from the backup server a backup copy for each document represented by a data object in the restore list of the document from the backup server; and

for each obtained backup copy replacing each document in the database corresponding to a data object in the restore list for which a respective backup copy is obtained.

26. The system of claim 25, wherein if a document represented by a data object in the restore list is marked as being unopenable then the unopenable document is restored by:

retrieving into the main memory a most recent backup copy of a document marked by the groupware server logic as being unopenable;

building the data object for the retrieved unopenable document;

storing the information from the data object describing the internal IDs of the backup copy into the main memory;

storing the backup copy in the document database;

reading the newly stored document from the database to compare its id with the id saved in main memory;

conditionally deleting the unopenable document from the database; and

replacing the unique document IDs of the backup copy stored in the document database with the internal IDs stored in main memory.

27. A computer program product for enabling back up and restore of at least one groupware document of a plurality of groupware documents stored in a groupware document database on a groupware document server having groupware server logic for use in a data processing system including a groupware document server having a plurality of documents stored in a groupware document database, a backup server coupled through a communications network to the groupware document server, main memory coupled to the groupware document server, each document containing zero or more data items and having an internal identifier (ID) that is used to identify the document to the groupware server logic and further having a database path identifying a storage location of the document, wherein the server logic is configured to allow viewing of documents stored in the database, the program product comprising:

a recording medium;

means, recorded on the recording medium for;

querying the groupware server logic to determine what items are contained in at least one specified document and what internal IDs are used to identify the at least one specified document to the groupware server logic;

building a data object for the at least one specified document that includes a data structure having a plurality of data fields, the plurality of data fields including zero or more item data fields containing information describing each item contained in the at least one specified document, at least one identifier field containing information describing internal IDs that are used to identify the particular document to the groupware server logic; and

using the data object to ensure data integrity of the particular document by enabling back up and restore operations that use the information contained in the data fields in the data object.

28. The computer program product of claim 27, wherein the means recorded on the recording medium for enabling back up operations include means for incrementally performing a backup of the groupware database by:

searching through the database to identify the documents that have been changed since the last back up operation;

specifying each document identified during the searching step, and in response to the specifying of a document building the data object;

sending each built data object to the backup server; and

performing a back up operation on the backup server using information contained in the sent data objects for each specified document.

29. The computer program product of claim 28, including means for searching to identify documents having accompanying deletion markers that indicate that the identified document is marked for deletion from the database.

30. The computer program product of claim 28, wherein a document is identified as changed if it has data that has been modified since the last back up operation.

31. The computer program product of claim 28, wherein a document is identified as changed if the document itself has been added since the last back up operation.

32. The computer program product of claim 28, wherein data has been modified if new data has been added to the document since the last back up operation.

33. The computer program product of claim 28, wherein a document is identified as changed if it has been marked to be deleted with a deletion stub.

34. The computer program product of claim 28, wherein the groupware server includes a plurality of document databases each having a plurality of documents and the computer program product performs the incremental back up on each database of the plurality of databases in a substantially simultaneous operation.

35. The computer program product of claim 29, further comprising means for notifying the backup server of identified documents having deletion markers that are to be deleted by the backup server.

36. The computer program product of claim 27, wherein the means recorded on the recording medium for enabling restore operations include operations to restore a document in the database that is marked as being unopenable by the groupware server logic by:

retrieving into the main memory a most recent backup copy of a document marked by the groupware server logic as being unopenable;

building the data object for the retrieved unopenable document;

storing the information from the data object describing the internal IDs of the backup copy into the main memory;

storing the backup copy in the document database;

reading the newly stored document from the database to compare its id with the id saved in main memory;

conditionally deleting the unopenable document from the database; and

replacing the unique document IDs of the backup copy stored in the document database with the internal IDs stored in main memory.

37. The computer program product of claim 27, wherein the means recorded on the recording medium for enabling restore operations include means for restoring an existing document by:

building the data object for a document selected for a document viewing operation;

retrieving into main memory a backup copy of the selected document from the backup server;

interpreting the information contained in the data object to reconstruct the document;

updating the backup copy in main memory with information from the reconstructed document; and

replacing the selected document with the backup copy in the database.

38. The computer program product of claim 27, wherein the means recorded on the recording medium for enabling restore operations include means for restoring a plurality of existing documents belonging to the groupware document database on the groupware server by:

building a plurality of the data objects, wherein each built data object represents an eligible backup copy of a document to be restored, wherein eligibility is determined by comparing a date and time record of when the backup copy was created to a predetermined date and time criterion;

creating a restore list containing each of the data objects representing eligible backup copies;

sorting the restore list to minimize potential mounts of media used by the backup server;

obtaining from the backup server a backup copy for each document represented by a data object in the restore list of the document from the backup server; and

for each obtained backup copy replacing each document in the database corresponding to a data object in the restore list for which a respective backup copy is obtained.

39. The computer program product of claim 38, wherein if a document represented by a data object in the restore list is marked as being unopenable then the unopenable document is restored by means for:

retrieving into the main memory a most recent backup copy of a document marked by the groupware server logic as being unopenable;

building the data object for the retrieved unopenable document;

storing the information from the data object describing the internal IDs of the backup copy into the main memory;

storing the backup copy in the document database;

reading the newly stored document from the database to compare its id with the id saved in main memory;

conditionally deleting the unopenable document from the database; and

replacing the unique document IDs of the backup copy stored in the document database with the internal IDs stored in main memory.

40. An apparatus for enabling back up and restore of at least one groupware document of a plurality of groupware documents stored in a groupware document database on a groupware document server having groupware server logic configured to communicate with a data processing system including a groupware document server having a plurality of documents stored in a groupware document database, a backup server coupled through a communications network to the groupware document server, each document containing at least one data item and having an internal identifier (ID) that is used to identify the document to the groupware server logic and further having a database path identifying a storage location of the document, wherein the server logic is configured to allow viewing of documents stored in the database, the apparatus comprising:

memory coupled to the groupware document server;

logic being loaded into the memory including;

a module configured to restore an existing document in the groupware document database;

a module configured to incrementally perform a back up of the groupware database to the backup server in order to back up only those documents in the database that have been changed since the most recent back up operation;

a module configured to restore a plurality of existing documents belonging to the groupware document database on the groupware server; and

a module configured to restore a document in the database that is marked as being unopenable by the groupware server logic.