Encoding a schema version in table names

• US 10,067,956 B2
• Filed: 07/31/2012
• Issued: 09/04/2018
• Est. Priority Date: 07/23/2010
• Status: Active Grant

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: Google LLC (Alphabet Inc.)
• Inventors: Bolohan, Matthew, Kroeger, Robert
• Primary Examiner(s): Jalil, Neveen Abel
• Assistant Examiner(s): Conyers, Dawaune
• Application Number:
  US13/563,465
• Publication Number:
  US 20120296884A1
• Time in Patent Office: 2,226 Days
• Field of Search: 707659
• CPC Class Codes: G06F 16/213 with details for schema evolution support
• CPC Class Codes: G06F 16/219 Managing data history or versioning querying versioned data G06F16/2474; querying temporal data G06F16/2477

Abstract

The subject matter of this disclosure can be implemented in, among other things, a device that includes processors, a data repository, and a table version module configured to create a first version of a database within the data repository using a first version of a database schema that defines a set of tables for the database, and receive a result that is responsive to a command, such that when the result indicates a success condition, execution of the command allows access to data contained in the database and verification of the database schema version, wherein the result does not include database schema version information. The device further includes means for executing the command to access the data, wherein the command includes one or more encoded table names, and wherein each of the encoded table names included in the command is generated based on at least a database schema version identifier.

Claims

1. A computer-readable storage medium encoded with instructions for causing one or more programmable processors to:

create a first version of a database using a first version of a database schema that defines a set of tables for the database;

without first performing an explicit database schema version check, execute a single command to verify a database schema version of the database and retrieve a set of access information contained in the database, wherein the single command includes one or more encoded table names, wherein each of the one or more encoded table names included in the single command is generated based on at least a first database schema version identifier, wherein the one or more encoded table names generated based on the first database schema version identifier that identifies the first version of the database schema for the database are different from one or more encoded table names generated based on a second database schema version identifier that identifies a second version of the database schema for the database, and wherein the first version of the database schema and the second version of the database schema are different database schemas for the database; and

receive a result that is responsive to the single command, such that, when at least one of the one or more encoded table names included in the single command corresponds to a name of a table of the database, the result

     1) indicates a success condition of the single command and

     2) includes the set of the information contained in the database.

2. The computer-readable storage medium of claim 1,

wherein each table of the set of tables of the database includes an encoded table name,

wherein the encoded table name of each table is generated based on an unencoded table name and the first database schema version identifier that identifies the first version of the database schema, and

wherein the result indicates a success condition when each of the one or more encoded table names included in the single command is generated based on one of the unencoded table names of the set of tables and on the first database schema version identifier that identifies the first version of the database schema.

3. The computer-readable storage medium of claim 2,

wherein the encoded table name of each table is generated by at least applying the first database schema version identifier to the corresponding unencoded table name to create a unique hash.

4. The computer-readable storage medium of claim 2,

wherein the encoded table name of each table includes a first portion and a second portion, wherein the first portion of each encoded table name includes the corresponding unencoded table name, and wherein the second portion of each encoded table name includes the first database schema version identifier.

5. The computer-readable storage medium of claim 1, further encoded with instructions for causing the one or more programmable processors to:

determine that the result indicates an error condition when each of the one or more encoded table names included in the single command is generated based on an unencoded table name and the second database schema version identifier that identifies the second version of the database schema; and

create a second version of the database using the second version of the database schema in response to determining that the result indicates the error condition.

6. The computer-readable storage medium of claim 5,

wherein the second version of the database schema defines a second set of tables each having an encoded table name,

wherein the encoded table name of each table in the second version of the database schema includes a first portion and a second portion,

wherein the first portion of each encoded table name in the second version of the database schema is the same as a first portion of the encoded table name of a corresponding table in the first version of the database schema, and

wherein the second portion of each encoded table name in the second version of the database schema includes the second database schema version identifier that identifies the second version of the database schema.

7. The computer-readable storage medium of claim 5, further encoded with instructions for causing the one or more programmable processors to retrieve the second version of the database schema from a server via a network.

8. The computer-readable storage medium of claim 5, further encoded with instructions for causing the one or more programmable processors to migrate information stored within the database created using the first version of the database schema to the second version of the database created using the second version of the database schema.

9. The computer-readable storage medium of claim 1, wherein the single command is an initial command of an application executed in response to application startup.

10. A method comprising:

creating a first version of a database using a first version of a database schema that defines a set of tables for the database;

without first performing an explicit database schema version check, executing a single command to verify a database schema version of the database and retrieve a set of access information contained in the database, wherein the single command includes one or more encoded table names, and wherein each of the one or more encoded table names included in the single command is generated based on at least a database schema version identifier, wherein the one or more encoded table names generated based on a first database schema version identifier that identifies the first version of the database schema for the database are different from one or more encoded table names generated based on a second database schema version identifier that identifies a second version of the database schema for the database, wherein the first version of the database schema and the second version of the database schema are different database schemas for the database; and

receiving a result that is responsive to the single command, such that, when at least one of the one or more encoded table names included in the single command corresponds to a name of a table of the database, the result

     1) indicates a success condition of the single command and

     2) includes the set of the information contained in the database.

11. The method of claim 10,

wherein each table of the set of tables of the database includes an encoded table name, wherein the encoded table name of each table is generated based on an unencoded table name and the first database schema version identifier that identifies the first version of the database schema, and

wherein the result indicates a success condition when each of the one or more encoded table names included in the single command is generated based on one of the unencoded table names of the set of tables and on the first database schema version identifier that identifies the first version of the database schema.

12. The method of claim 11, wherein the encoded table name of each table is generated by at least applying the first database schema version identifier to the corresponding unencoded table name to create a unique hash.

13. The method of claim 11, wherein the encoded table name of each table includes a first portion and a second portion, wherein the first portion of each encoded table name includes the corresponding unencoded table name, and wherein the second portion of each encoded table name includes the first database schema version identifier.

14. The method of claim 10, further comprising:

determining that the result indicates an error condition, wherein each of the one or more encoded table names included in the single command is generated based on an unencoded table name and the second database schema version identifier that identifies the second version of the database schema that is different from the first version of the database schema; and

creating a second version of the database using the second version of the database schema in response to determining that the result indicates the error condition.

15. The method of claim 14,

wherein the second version of the database schema defines a second set of tables each having an encoded table name,

wherein the encoded table name of each table in the second version of the database schema includes a first portion and a second portion,

wherein the first portion of each encoded table name in the second version of the database schema is the same as a first portion of the encoded table name of a corresponding table in the first version of the database schema, and

wherein the second portion of each encoded table name in the second version of the database schema includes the second database schema version identifier that identifies the second version of the source database schema.

16. The method of claim 10, wherein the single command is an initial command of an application executed in response to application startup.

17. A device comprising:

one or more processors;

a data repository configured to store information;

a table version module operable by the one or more processors to create a first version of a database within the data repository using a first version of a database schema, wherein the first version of the database schema defines a set of tables for the database; and

an application operable by the one or more processors to, without first performing an explicit database schema version check, execute a single command to verify a database schema version of the database and retrieve a set of access information contained in the database, wherein the single command includes one or more encoded table names, wherein each of the one or more encoded table names included in the single command is generated based on at least a database schema version identifier, wherein the one or more encoded table names generated based on a first database schema version identifier that identifies the first version of the database schema for the database are different from one or more encoded table names generated based on a second database schema version identifier that identifies a second version of the database schema for the database, and wherein the first version of the database schema and the second version of the database schema are different database schemas for the database, and

wherein the table version module is further operable by the one or more processors to receive a result that is responsive to the single command, such that when at least one of the one or more encoded table names included in the single command corresponds to a name of a table of the database, the result

     1) indicates a success condition of the single command and

     2) includes a set of the information contained in the database.

18. The device of claim 17,

wherein each table of the set of tables of the database includes an encoded table name, wherein the encoded table name of each table is generated based on an unencoded table name and the first database schema version identifier that identifies the first version of the database schema, and

wherein the result indicates a success condition when each of the one or more encoded table names included in the single command is generated based on one of the unencoded table names of the set of tables and on the first database schema version identifier that identifies the first version of the database schema.

19. The device of claim 17, wherein the table version module is further configured to determine that the result indicates an error condition, wherein each of the one or more encoded table names included in the single command is generated based on an unencoded table name and the second database schema version identifier that identifies the second version of the database schema, and create a second version of the database using the second version of the database schema in response to determining that the result indicates the error condition.

20. The device of claim 19,

wherein the second version of the database schema defines a second set of tables each having an encoded table name,

wherein the encoded table name of each table in the second version of the database schema includes a first portion and a second portion,

wherein the first portion of each encoded table name in the second version of the database schema is the same as a first portion of the encoded table name of a corresponding table in the first version of the database schema, and

wherein the second portion of each encoded table name in the second version of the database schema includes the second database schema version identifier that identifies the second version of the source database schema.