Table level database restore in a data storage system

• US 10,997,038 B2
• Filed: 08/15/2017
• Issued: 05/04/2021
• Est. Priority Date: 01/11/2013
• Status: Active Grant

• Current Assignee: CommVault Systems Incorporated
• Original Assignee: CommVault Systems Incorporated
• Inventors: Kumarasamy, Paramasivam, Vallabhaneni, Brahmaiah
• Primary Examiner(s): Skhoun, Hicham
• Application Number:
  US15/677,898
• Publication Number:
  US 20180089038A1
• Time in Patent Office: 1,358 Days
• Field of Search: 707679
• CPC Class Codes: G06F 11/1448 Management of the data involved in backup or backup restore
• CPC Class Codes: G06F 11/1469 Backup restoration techniques
• CPC Class Codes: G06F 2201/80 Database-specific techniques

Abstract

The data storage system according to certain aspects can implement table level database restore. Table level database restore may refer to restoring a database table and its related data without restoring the entire database. The data storage system may use table metadata index to implement table level restore. A table metadata index may be created for each table, e.g., during a backup of the database. The table metadata index for a table can include any type of information for restoring the table and its related data. Some examples of the type of information included in the table metadata index include the following: container for the table, table backup location, system data, table index, table relationships, etc. Table metadata index can make the restoring of tables fast and efficient by packaging information that can be used to restore a table and its related data in an easily accessible manner.

Claims

1. A method of storing database tables in secondary storage of a data storage system, comprising:

using one or more computing devices comprising computer hardware;

backing up a database comprising a plurality of database tables wherein the plurality of database tables comprises a first database table and a second database table wherein the second database table is different from the first database table, wherein the backing up comprises copying data associated with the plurality of database tables from one or more primary storage devices in a primary storage subsystem to one or more secondary storage devices in a secondary storage subsystem, wherein said copying comprises at least;

determining a first set of database tables from the plurality of database tables, wherein each one of the database tables in the first set of database tables is referenced by the first database table; and

creating a separate first table metadata index for the first database table that is distinct from a plurality of table metadata indexes associated with each one of the plurality of database tables in the database, wherein the first table metadata index comprises, (i) a relationship information of the first database table to each one of the database tables in the determined first set of database tables that is referenced by the first database table; and

(ii) metadata for restoring the first database table and its related data to the primary storage subsystem from the secondary storage subsystem; and

wherein the first table metadata index is specific to the first database table for use in restoring the first database table and the database tables in the first set of database tables, without restoring or accessing all the other database tables in the database or accessing table metadata indexes associated with each one of the plurality of database tables in the database; and

determining, from the plurality of database tables, a second set of database tables referenced by the second database table different from the first database table; and

creating a separate second table metadata index that is distinct from the plurality of table metadata indexes associated with each one of the plurality of database tables in the database, wherein the second table metadata index comprises (a) a relationship information of the second database table to each one of the database tables in the determined second set of database tables and (b) metadata for restoring each one of the database tables in the identified second set of database tables to the one or more primary storage devices from the secondary storage subsystem; and

wherein the second table metadata index is specific to the second database table for use in restoring the second database table without restoring all the other database tables in the database or accessing table metadata indexes associated with each one of the plurality of database tables in the database.

2. The method of claim 1, further comprising restoring the first database table from the secondary storage subsystem to the primary storage subsystem at least by accessing the first table metadata index, without restoring the second database table or accessing the second table metadata index.

3. The method of claim 2, wherein subsequent to said restoring, data associated with the first set of database tables referenced by the first database table are accessible in the primary storage subsystem.

4. The method of claim 1, further comprising storing the first table metadata index in a data structure associated with one or more storage managers comprising computer hardware wherein the first table metadata index is stored separately from the data associated with the plurality of database tables.

5. The method of claim 1, further comprising storing the first table metadata index in a data structure associated with one or more media agents comprising computer hardware wherein the first table metadata index is stored separately from the data associated with the plurality of database tables.

6. The method of claim 1, further comprising storing the first table metadata index on the one or more secondary storage devices, wherein the first table metadata index is stored together with the data associated with the plurality of database tables.

7. The method of claim 1, wherein the backing up of the database comprising a plurality of database tables is made during a scheduled backup of primary data from the primary storage subsystem to the secondary storage subsystem.

8. The method of claim 1, wherein the first table metadata index comprises metadata relating to the first set of database tables, the metadata comprising, for each respective database table in the first set, a table metadata index usable to restore the respective database table.

9. The method of claim 1, wherein the first table metadata index comprises a list including the first set of database tables referenced by the first database table.

16. The method of claim 1, wherein the first table metadata index and the second table metadata index are not stored in the secondary storage subsystem.

17. The method of claim 1, wherein the first table metadata index comprises information relating to one or more of:

a container for the first database table, a tablespace for the first database table, a table schema of the first database table, a backup location of the first database table in the secondary storage subsystem, system data associated with the first database table, and a table index associated with the first database table.

18. The method of claim 1, wherein the second table metadata index comprises information relating to one or more of:

a container for the second database table, a tablespace for the second database table, a table schema of the second database table, a backup location of the second database table in the secondary storage subsystem, system data associated with the second database table, and a table index associated with the second database table.

19. The method of claim 1, wherein the relationship between the first database table and the first set of database tables of the plurality of database tables is determined by a table level restore module.

20. The method of claim 1, wherein the first table metadata index further comprises information for restoring one or more of:

a system object referenced by the first table and a database object referenced by the first table.

10. A system for storing database tables, comprising:

one or more computing devices comprising computer hardware and configured to;

copy data associated with a plurality of database tables from one or more primary storage devices in a primary storage subsystem to one or more secondary storage devices in a secondary storage subsystem, wherein the plurality of database tables comprises a first database table and a second database table that is different from the first database table, and wherein the one or more computing devices are configured to copy the data at least by;

determining a first set of database tables from the plurality of database tables, wherein each one of the database tables in the first set of database tables is referenced by the first database table; and

creating a separate first table metadata index for the first database table that is distinct from a plurality of table metadata indexes associated with each one of the plurality of database tables in the database, wherein the first table metadata index comprises, (i) a relationship information of the first database table to each one of the database tables in the determined first set of database tables that is referenced by the first database table; and

(ii) metadata for restoring the first database table and its related data to the primary storage subsystem from the secondary storage subsystem; and

wherein the first table metadata index is specific to the first database table for use in restoring the first database table and the database tables in the first set of database tables, without restoring or accessing all the other database tables in the database or accessing the table metadata indexes associated with each one of the plurality of database tables in the database; and

determining, from the plurality of database tables, a second set of database tables referenced by the second database table different from the first database table; and

creating a separate second table metadata index that is distinct from the plurality of table metadata indexes associated with each one of the plurality of database tables in the database, wherein the second table metadata index comprises (a) a relationship information of the second database table to each one of the database tables in the determined second set of database tables and (b) metadata for restoring each one of the database tables in the determined second set of database tables to the primary storage subsystem from the secondary storage subsystem; and

wherein the second table metadata index is specific to the second database table for use in restoring the second database table without restoring or accessing all the other database tables in the database or accessing the table metadata indexes associated with each one of the plurality of database tables in the database.

11. The system of claim 10, wherein the one or more computing devices are further configured to restore the first database table from the secondary storage subsystem to the primary storage subsystem at least by accessing the first table metadata index, without restoring the second database table or accessing the second table metadata index.

12. The system of claim 11, wherein subsequent to said restoring, data associated with the first set of database tables referenced by the first database table are accessible in the primary storage subsystem.

13. The system of claim 10, wherein the one or more computing devices are further configured to store the first table metadata index in a data structure associated with one or more storage managers comprising computer hardware or one or more media agents comprising computer hardware wherein the first table metadata index is stored separately from the data associated with the plurality of database tables.

14. The system of claim 10, wherein the one or more computing devices are further configured to store the first table metadata index on the one or more secondary storage devices wherein the first table metadata index is stored together with the data associated with the plurality of database tables.

15. The system of claim 10, wherein the one or more computing devices are further configured to determine the first set of database tables and to create the first table metadata index during a scheduled backup of primary data from the primary storage subsystem to the secondary storage subsystem.