Asynchronous shared application upgrade

• US 10,635,658 B2
• Filed: 09/15/2016
• Issued: 04/28/2020
• Est. Priority Date: 10/23/2015
• Status: Active Grant

• Current Assignee: Oracle International Corporation (Oracle Corporation)
• Original Assignee: Oracle International Corporation (Oracle Corporation)
• Inventors: Yam, Philip, Baby, Thomas, Kruglikov, Andre, Rajamani, Kumar
• Primary Examiner(s): Skhoun, Hicham
• Application Number:
  US15/266,917
• Publication Number:
  US 20180075086A1
• Time in Patent Office: 1,321 Days
• Field of Search: 707684
• CPC Class Codes: G06F 11/1474 in transactions G06F16/20 takes precedence
• CPC Class Codes: G06F 16/2379 Updates performed during online database operations; commit processing
• CPC Class Codes: G06F 2201/87 Monitoring of transactions
• CPC Class Codes: G06F 8/65 Updates security arrangements therefor G06F21/57

Abstract

Techniques are provided for diverting, to cloned metadata, live access to original metadata of an application container that is being concurrently upgraded. In an embodiment, a database server stores, within an application container of an application, original metadata that defines objects for use by pluggable databases of the application. The database server receives a maintenance request to adjust the original metadata. The database server creates, in response to receiving the maintenance request, a reference container that contains cloned metadata that is a copy of the original metadata. The database server receives, during or after creating the reference container, a read request to read one of the objects. The database server concurrently performs both of: executing the maintenance request upon the original metadata, and executing the read request upon the cloned metadata of the reference container.

Claims

1. A method comprising:

storing, within an original application container database of a database application, original metadata that defines one or more objects for use by a plurality of pluggable databases of the database application that reside in the original application container database;

receiving a maintenance request to adjust the original metadata;

creating, in response to receiving the maintenance request to adjust the original metadata, a reference application container database that contains cloned metadata that is a copy of the original metadata, wherein a container database contains a plurality of application container databases that includes the original application container database and the reference application container database;

receiving, during or after creating the reference application container database, a read request to read an object of the one or more objects;

concurrently performing both of;

adjusting the original metadata in the original application container database by executing the maintenance request, and

executing the read request upon the cloned metadata of the reference application container database;

updating, based on said adjusting the original metadata, a database dictionary of at least one pluggable database of the plurality of pluggable databases.

2. The method of claim 1 wherein creating the reference application container database comprises associating the original application container database or the original metadata to an identifier of the reference application container database or an identifier of the cloned metadata.

3. The method of claim 1 wherein executing the maintenance request comprises:

issuing one or more database statements to the original application container database, and

creating a recording of the one or more database statements;

issuing the one or more database statements to at least one pluggable database of said plurality of pluggable databases by replaying the recording.

4. The method of claim 1 wherein creating the reference application container database comprises making the reference application container database consistent by applying an undo record to roll back a transaction.

5. The method of claim 4 wherein:

creating the reference application container database comprises assigning a new identifier to an object within the reference application container database;

the undo record contains an old identifier of the object;

applying the undo record comprises translating the old identifier into the new identifier.

6. The method of claim 1 further comprising:

receiving, after executing the maintenance request, an additional request to read the original metadata;

executing the additional request upon the original metadata of the original application container database.

7. The method of claim 6 wherein after executing the maintenance request comprises after receiving a command to cease using the reference application container database.

8. The method of claim 1 wherein the reference application container database is read only or does not accept client connections.

9. The method of claim 1 wherein executing the maintenance request comprises creating or modifying a database view that hides a subset of the original metadata.

10. The method of claim 1 wherein the cloned metadata comprises one or more metadata rows contained in one or more relational tables.

11. A system comprising:

database storage configured to store and retrieve, within an original application container database of a database application, original metadata that defines one or more objects for use by a plurality of pluggable databases of the database application that reside in the original application container database;

a processor connected to the database storage and configured to;

receive a maintenance request to adjust the original metadata;

create, in response to receiving the maintenance request to adjust the original metadata and within the database storage, a reference application container database that contains cloned metadata that is a copy of the original metadata, wherein a container database contains a plurality of application container databases that includes the original application container database and the reference application container database;

receive, during or after creating the reference application container database, a read request to read an object of the one or more objects;

concurrently perform both of;

adjusting the original metadata in the original application container database by executing the maintenance request upon the original metadata, and

executing the read request upon the cloned metadata of the reference application container database;

updating, based on said adjusting the original metadata, a database dictionary of at least one pluggable database of the plurality of pluggable databases.

12. One or more non-transitory computer-readable media storing instructions that, when executed by one or more processors, cause:

storing, within an original application container database of a database application, original metadata that defines one or more objects for use by a plurality of pluggable databases of the database application that reside in the original application container database;

receiving a maintenance request to adjust the original metadata;

creating, in response to receiving the maintenance request to adjust the original metadata, a reference application container database that contains cloned metadata that is a copy of the original metadata, wherein a container database contains a plurality of application container databases that includes the original application container database and the reference application container database;

receiving, during or after creating the reference application container database, a read request to read an object of the one or more objects;

concurrently performing both of;

adjusting the original metadata in the original application container database by executing the maintenance request upon the original metadata, and

executing the read request upon the cloned metadata of the reference application container database;

updating, based on said adjusting the original metadata, a database dictionary of at least one pluggable database of the plurality of pluggable databases.

13. The one or more non-transitory computer-readable media of claim 12 wherein creating the reference application container database comprises associating the original application container database or the original metadata to an identifier of the reference application container database or an identifier of the cloned metadata.

14. The one or more non-transitory computer-readable media of claim 12 wherein creating the reference application container database comprises making the reference application container database consistent by applying an undo record to roll back a transaction.

15. The one or more non-transitory computer-readable media of claim 14 wherein:

creating the reference application container database comprises assigning a new identifier to an object within the reference application container database;

the undo record contains an old identifier of the object;

applying the undo record comprises translating the old identifier into the new identifier.

16. The one or more non-transitory computer-readable media of claim 12 wherein the instructions further cause:

receiving, after executing the maintenance request, an additional request to read the original metadata;

executing the additional request upon the original metadata of the original application container database.

17. The one or more non-transitory computer-readable media of claim 16 wherein after executing the maintenance request comprises after receiving a command to cease using the reference application container database.

18. The one or more non-transitory computer-readable media of claim 12 wherein executing the maintenance request comprises creating or modifying a database view that hides a subset of the original metadata.

19. The one or more non-transitory computer-readable media of claim 12 wherein executing the maintenance request comprises:

issuing one or more database statements to the original application container database, and

creating a recording of the one or more database statements;

issuing the one or more database statements to at least one pluggable database of said plurality of pluggable databases by replaying the recording.