Method and mechanism for supporting virtual content in performing file operations at a RDBMS

• US 20070005555A1
• Filed: 06/29/2005
• Published: 01/04/2007
• Est. Priority Date: 06/29/2005
• Status: Active Grant

• Current Assignee: Oracle International Corporation (Oracle Corporation)
• Original Assignee: Oracle International Corporation (Oracle Corporation)
• Inventors: Jain, Namit, Murthy, Ravi, Agarwal, Nipun, Pannala, Syam, Kapoor, Vikram
• Granted Patent: US 8,224,837 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/1774 Locking methods, e.g. locking methods for file systems allowing shared and concurrent access to files
• CPC Class Codes: G06F 16/188 Virtual file systems

Abstract

Techniques are provided for accessing and storing files within a virtual folder. A virtual folder is a folder that is logically a part of a hierarchical folder structure of a file system repository, but the contents of the virtual folder are not physically stored in the file system repository. A client may issue, to an access mechanism, a request to perform a file operation on a file in a virtual folder. The access mechanism, which may be a database server or a component therein, may perform the file operation on the file in the virtual folder as if the file was stored in a particular folder within the hierarchical folder structure implemented by the file system repository. Advantageously, files may be physically stored outside of the file system repository, but still be a part of the hierarchical folder structure implemented by the file system repository.

Claims

1. A machine-implemented method for accessing one or more files, comprising:

submitting NFS commands to an access mechanism to store a plurality of files in folders within a hierarchical folder structure implemented by a repository; and

submitting an NFS command to the access mechanism to access a file that is not stored in said repository as if said file was stored in a particular folder within the hierarchical folder structure that is implemented by said repository.

2. The method of claim 1, wherein the access mechanism is a database server, and said repository is implemented by a database.

3. The method of claim 1, further comprising:

obtaining an identifier that uniquely identifies the file to the access mechanism; and

generating a NFS filehandle for said file based, at least in part, on the identifier.

4. The method of claim 3, further comprising:

registering a callback function, provided by an external entity responsible for providing access to said file, with the access mechanism, wherein execution of said callback function retrieves said file and said identifier from said external entity.

5. The method of claim 3, wherein said step of obtaining an identifier is performed by accessing information, maintained by a database that is implementing said repository, identifying items stored in said database.

6. The method of claim 1, further comprising:

submitting a second NFS command to said access mechanism to create a virtual folder, within said hierarchical folder structure, by registering one or more callback functions for the virtual folder with the access mechanism.

7. The method of claim 1, wherein the step of submitting the NFS command to the access mechanism comprises one or more of the following steps:

a server submitting the NFS command to a component responsible for accessing files not stored in the repository as if the files were stored within the hierarchical folder structure that is implemented by the repository; and

a client submitting the NFS command to the access mechanism.

8. The method of claim 1, further comprising:

performing a lock operation on said file using the same lock mechanism as if said file was stored within said hierarchical folder structure.

9. The method of claim 1, further comprising:

performing a security operation on said file using the same security mechanism as if said file was stored within said hierarchical folder structure.

10. A machine-readable medium carrying one or more sequences of instructions for accessing one or more files, wherein execution of the one or more sequences of instructions by one or more processors causes the one or more processors to perform the steps of:

submitting NFS commands to an access mechanism to store a plurality of files in folders within a hierarchical folder structure implemented by a repository; and

submitting an NFS command to the access mechanism to access a file that is not stored in said repository as if said file was stored in a particular folder within the hierarchical folder structure that is implemented by said repository.

11. The machine-readable medium of claim 10, wherein the access mechanism is a database server, and said repository is implemented by a database.

12. The machine-readable medium of claim 10, wherein execution of the one or more sequences of instructions by the one or more processors further causes the one or more processors to perform the steps of:

obtaining an identifier that uniquely identifies the file to the access mechanism; and

generating a NFS filehandle for said file based, at least in part, on the identifier.

13. The machine-readable medium of claim 12, wherein execution of the one or more sequences of instructions by the one or more processors further causes the one or more processors to perform the step of:

registering a callback function, provided by an external entity responsible for providing access to said file, with the access mechanism, wherein execution of said callback function retrieves said file and said identifier from said external entity.

14. The machine-readable medium of claim 12, wherein said step of obtaining an identifier is performed by accessing information, maintained by a database that is implementing said repository, identifying items stored in said database.

15. The machine-readable medium of claim 10, wherein execution of the one or more sequences of instructions by the one or more processors further causes the one or more processors to perform the step of:

submitting a second NFS command to said access mechanism to create a virtual folder, within said hierarchical folder structure, by registering one or more callback functions for the virtual folder with the access mechanism.

16. The machine-readable medium of claim 10, wherein the step of submitting the NFS command to the access mechanism comprises one or more of the following steps:

a server submitting the NFS command to a component responsible for accessing files not stored in the repository as if the files were stored within the hierarchical folder structure that is implemented by the repository; and

a client submitting the NFS command to the access mechanism.

17. The machine-readable medium of claim 10, wherein execution of the one or more sequences of instructions by the one or more processors further causes the one or more processors to perform the step of:

performing a lock operation on said file using the same lock mechanism as if said file was stored within said hierarchical folder structure.

18. The machine-readable medium of claim 10, wherein execution of the one or more sequences of instructions by the one or more processors further causes the one or more processors to perform the step of:

performing a security operation on said file using the same security mechanism as if said file was stored within said hierarchical folder structure.