Remote Container

• US 20120042174A1
• Filed: 08/13/2010
• Published: 02/16/2012
• Est. Priority Date: 08/13/2010
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Zaydman, Oleg, Maeckel, Clay, Crumly, Lyndley
• Granted Patent: US 8,688,585 B2
• Time in Patent Office: Days
• US Class Current: 713/189
• CPC Class Codes: G06F 16/20 of structured data, e.g. relational data

Abstract

Methods, program products, and systems implementing remote container techniques are disclosed. A relational database can include a container data field, which can be a data field for storing multimedia data. In one aspect, when the multimedia data are inserted into the container field, the multimedia data can be stored in one or more remote database files. The remote database files can be located separately from other data of the relational database and remotely from a client computer accessing the relational database. Corresponding data structures, or remote containers, can be configured to store metadata of the database files. References to the remote containers can be stored as values of the container data field. Using various encryption techniques, the remote database files can be given same access restrictions as access restrictions of the container data field, even when the remote database files are stored as flat files.

Claims

1. A method comprising:

receiving data to be inserted into a container data field of a relational database;

storing the data in a database file at a location specified for the container data field, the database file being external to other database files storing data of other data fields of the relational database;

storing a reference to the database file in a first portion of a remote container; and

associating the remote container with the container data field.

2. The method of claim 1, wherein the container data field is configured to store content of at least one of a data stream, a binary object, or a file.

3. The method of claim 1, wherein:

the remote container includes a data structure configured to store information, including access restrictions information, of the database file; and

associating the remote container with the container data field includes storing a reference to the remote container in the container data field.

4. The method of claim 1, further comprising determining an access restriction of the database file based on an access restriction of the container data field.

5. The method of claim 4, where determining the access restriction of the database file comprises:

encrypting the database file using an encryption key that is specific to the container data field; and

storing the encryption key in a second portion of the remote container.

6. The method of claim 1, further comprising:

receiving first new data and second new data, in that order, to be inserted into the container data field to replace the stored data;

creating a first temporary remote container that corresponds to the first new data, and a second temporary remote container that corresponds to the second new data;

receiving a transactional input, the transactional input including one of a commit input, an undo input, or a revert input;

associating the second temporary remote container with the container data field when the transactional input is a commit input;

associating the first temporary remote container with the container data field when the transactional input is an undo input; and

clearing the first temporary remote container and second temporary remote container when the transactional input is a revert input.

7. The method of claim 1, wherein:

storing the data in the database file includes;

identifying existing data that are stored in an existing database file, the existing database file referenced by an existing remote container;

determining that the existing data are identical to the received data; and

upon the determining, incrementing a reference count of the existing remote container; and

associating the remote container with the container data field includes associating the existing remote container with the container data field.

8. The method of claim 7, wherein determining that the existing data are identical to the received data includes:

calculating a hash value of the existing data;

calculating a hash value of the received data; and

determining that the existing data are identical to the received data when the hash value of the existing data is equal to the hash value of the received data.

9. The method of claim 1, further comprising determining that the database file is modified external to a transaction of the relational database, including:

calculating an original hash value of the data;

storing the original hash value of the data in a third portion of the remote container; and

when the container data field is accessed;

determining that the data are not currently stored in a cache;

reading the data into the cache;

calculating a new hash value of the data read into the cache; and

determining that the database file is modified external to a transaction of the relational database when the original hash value and the new hash value do not match.

10. The method of claim 1, wherein storing the data in the database file includes:

creating a subdirectory at the location specified for the container data field according to a random distribution calculated base at least in part on the data; and

storing the database file in the subdirectory.

11. The method of claim 10, wherein creating the subdirectory at the location according to the random distribution includes:

calculating a hash value of at least one of the database file or metadata of the database file;

creating the subdirectory at the location specified for the container data field based on a partition of the hash value; and

assigning a portion of the hash value as a name of the subdirectory.

12. The method of claim 11, wherein creating the subdirectory based on the partitioning of the hash value includes:

identifying a first portion and a second portion of the hash value, the second portion of the hash value being different from the first portion of the hash value;

creating a first level subdirectory according to the first portion of the hash value; and

creating a second level subdirectory according to a second portion of the hash, wherein the second level subdirectory is a subdirectory of the first level subdirectory.

13. The method of claim 12, where each of the first portion and second portion of the hash value includes two hexadecimal characters limiting a number of first level subdirectories and a number of second level subdirectories to 256 each.

14. The method of claim 1, wherein storing the data in the database file includes storing the database file in a directory, the directory including a relative path determined according to a calculation formula.

15. The method of claim 14, wherein storing data in the database file includes:

resolving the calculation formula using inputs including at least one of a system variable or a value of another data field of the relational database; and

storing the resolved formula in a fourth portion of the remote container.

16. The method of claim 1, wherein:

storing the data in the database file includes creating a file name of the database file that is unique at the location specified for the container data field; and

storing the reference to the database file includes storing the unique file name in the first portion of the remote container.

17. The method of claim 1, further comprising:

storing the remote container in a container repository together with an embedded container; and

storing an identifier of the remote container as a value of the container data field.

18. The method of claim 1, further comprising storing an original file name of the data in a fifth portion of the remote container.

19. The method of claim 1, further comprising storing the location specified for the container data field in a sixth portion of the remote container.

20. A computer program product stored on a storage device, operable to cause one or more processors to perform operations comprising:

receiving data to be inserted into a container data field of a relational database;

storing the data in a database file at a location specified for the container data field, the database file being external to other database files storing data of other data fields of the relational database;

storing a reference to the database file in a first portion of a remote container; and

associating the remote container with the container data field.

21. The product of claim 20, wherein the container data field is configured to store multimedia content.

22. The product of claim 20, wherein:

the remote container includes a data structure configured to store metadata of the database file; and

associating the remote container with the container data field includes storing a reference to the remote container in the container data field.

23. A system comprising:

one or more processors configured to perform operations comprising;

receiving data to be inserted into a container data field of a relational database;

storing the data in a database file at a location specified for the container data field, the database file being external to other database files storing data of other data fields of the relational database;

storing a reference to the database file in a first portion of a remote container; and

associating the remote container with the container data field.

24. The system of claim 23, the operations further comprising determining an access restriction of the database file based on an access restriction of the container data field.