Patent Abstract:
The present invention provides a system and method of synchronizing a cache that substantially eliminates or reduces disadvantages associated with previously developed systems and methods of synchronizing caches. More particularly, embodiments of the present invention provide a system and method for bi-directional synchronization of a cache. One embodiment of the system of this invention includes a software program stored on a computer readable medium. The software program can be executed by a computer processor to run in user space and perform steps comprising: receiving a database asset from a database; storing the database asset as a cached file in a cache; determining if the cached file has been modified; and if the cached file has been modified, communicate the cached file directly to the database. In one embodiment of the present invention, the software program can determine if the cached file has been modified through automatic notification from a file management system. Alternatively, the software program can poll a cached file to determine if the cached file has changed. In another embodiment of the present invention, the software program can be further executable to perform the step of prompting an operating system to open the cached file in an application associated with the cached file&#39;s file type. In yet another embodiment of the present invention, the software program can be further executable to receive notifications from a database of when contention for a database asset occurs. Thus, bi-directional synchronization can occur.

Full Description:
RELATED APPLICATIONS 
     This application is a continuation of and claims priority under 35 U.S.C. §120 to U.S. patent application Ser. No. 11/328,526, U.S. Pat. No. 7,590,665, filed Jan. 10, 2006, entitled “SYSTEM AND METHOD FOR THE SYNCHRONIZATION OF A FILE IN A CACHE”, by David Thomas et al., which in claims priority under 35 U.S.C. §120 to U.S. patent application Ser. No. 10/033,242, U.S. Pat. No. 7,062,515, filed Dec. 28, 2001, entitled “SYSTEM AND METHOD FOR THE SYNCHRONIZATION OF A FILE IN A CACHE” by David Thomas et al., which is hereby fully incorporated by reference herein. 
    
    
     TECHNICAL FIELD OF THE INVENTION 
     This invention relates generally to cache management and more particularly to a system and method of synchronizing a cached file with a database. 
     BACKGROUND OF THE INVENTION 
     Centralized databases are becoming increasingly popular for storing electronic files or “database assets.” Most databases are operated under a client/server computer network model. In a client/server network, a client computer requests information (e.g., makes a request for files or database assets, etc.) from a server computer. In response to the request, the server computer searches the database for the requested information, retrieves the information, and communicates the information to the requesting client computer. 
     Having a general repository of information such as a database is advantageous because it allows multiple users to access the same file from various client computers, thereby allowing, for example, employees from disparate departments to work together on the same project, thus promoting efficiency and teamwork. Furthermore, because employees can access the database from remote computers via a network (e.g., LAN, Internet, etc.), the employee can access and work on files from home or while “on the road.” Thus, databases help support employee mobility and even the most mobile employees can work with database assets so long as the employee can establish a network connection to a database server (e.g., the computer responsible for handling database requests). 
     Additionally, databases free organizations from relying on individual users to store files on local machines. Using a centralized database to store files can decrease the likelihood that a file will be lost or corrupted if an employee misplaces or damages his/her computer. Yet another advantage provided by centralized databases is that an organization can control user access to particular database assets. Through authentication and authorization (validation) processes, such as requiring user names and/or passwords, an organization can govern which employees can work with particular files. This can help in controlling of work product and in ensuring quality control. 
     Because database assets are typically transported over a relatively slow network connection, a cache at a user&#39;s computer can be used to increase the speed with which files can be accessed and modified. A cache typically stores a local copy of a database asset on the user&#39;s computer. Thus a user can access and modify a local copy of a file, which is generally much faster than accessing a file directly over a network. When a user makes a change to the local or “cached” file copy, the change can, as will be described below, be synchronized with the database from which the file was originally retrieved. 
     Despite the many advantages provided by databases, databases also present many challenges to organizations. Typically, an organization&#39;s database(s) include a myriad of different database asset types. For example, a corporation&#39;s database might include Microsoft™ Word™ files, Microsoft™ Excel™ files, WordPerfect™ files, text files, graphics files (e.g., .jpg, .tif, or .gif), html files, AutoCAD™ files, etc. In addition to storing multiple types of database assets, there may also be a number of different users trying to access the same files. 
     Adding to the complexity of database management, various users of database assets may prefer to use different tools (e.g., they will have a “tool of choice)” to modify different types of database assets. Thus, for example, one user may prefer to use Microsoft™ Word™ to edit word processing documents while another user may prefer a different text editor. Therefore, in managing a network incorporating a database, an organization must be able to reconcile the multifarious subjective user preferences. 
     Several systems have been developed in an attempt to meet the challenges presented by database management. One current system requires that users employ custom-designed tools in order to edit the assets in a database. While the custom-designed tools typically reduce latency by automatically saving changes or modifications to the database, these systems are unattractive because they do not allow a user to seamlessly employ his/her tool of choice. Instead, the user must utilize a tool provided by the database vendor or an external editor that is typically cumbersome to use. Because he/she may not be familiar or efficient with the tool, the user may require extra training and, consequently, this can result in extra expense to the employer or other organization. 
     A second option that is currently available allows a user to utilize standard software tools (e.g., Microsoft™ Word™) to access and modify database assets, but requires a second program (a “synchronization program”) on the client machine to synchronize any modifications that a user makes on his/her client machine with the database. These systems, also have several shortcomings. Primarily, synchronization programs are typically designed to run with only one software tool (e.g., they act as a plug-in to an existing software application) or, if designed to run with multiple programs, they require significant amounts of additional coding. Thus, a user will be able to use only the tools for which the organization has a synchronization program in place. Therefore, a user&#39;s choice in software is severely limited by the presence or absence of a synchronization program. Furthermore, these prior art systems typically require that the user take extra steps in saving data to the database. When a user saves a file on his/her local (e.g., client) machine, he/she typically must also save the file in the synchronization program in order to have the file saved to the database. While it may only take an additional few seconds to save a file to the database using the synchronization program (though it can take significantly longer, particularly to save large files to a remote database), over the course of many saves this can lead to significant losses in time and productivity. These systems are also deficient because they can lead to significant latency problems. If a user forgets to perform the extra step of saving a file to the database using the synchronization program, any modifications that the user saved using a local program or tool will only be saved locally and will not be reflected on the database until the user synchronizes the local file with the database. Thus, if a user forgets to save a file to the database using the synchronization program, the database will not contain the latest version of a file for a potentially long period of time. Consequently, if another user access the file from the database before synchronization occurs, he or she will not receive up-to-date information. 
     Yet another existing system for accessing and modifying database assets that has been developed is an operating system-level implementation that creates a file system on a local machine (e.g., a user&#39;s computer or client computer), that allows the user to view database assets as if the assets were locally situated. In this system, the user sees the database reflected as an additional virtual local storage device (e.g., an “E” drive). Database assets are depicted as files on the file system. When a user selects the database asset that he/she wants to edit (e.g., by double clicking on the asset), the database asset can be retrieved from the database and can be opened locally with whichever program is associated with that particular type of asset (e.g., Adobe® PhotoShop could open .jpg files). This system presents shortcomings, however, because it requires additional programming at the operating system “driver” level. Any defect or error in the program while the program is running can cause the local user&#39;s machine to cease functioning or “crash” until the operating system is reinitialized (e.g., until the client computer is rebooted), significantly reducing user productivity, and leading to loss of data. 
     SUMMARY OF THE INVENTION 
     The present invention provides a system and method of synchronizing a cache that substantially eliminates or reduces disadvantages associated with previously developed systems and methods of synchronizing caches. More particularly, embodiments of the present invention provide a system and method for bi-directional synchronization of a cache. An embodiment of the system of this invention includes a software program stored on a computer readable medium. The software programming can be executable by a computer processor to run in user space and perform steps comprising: receiving a database asset from a database; storing the database asset as a cached file in a cache; determining if the cached file has been modified; and, if the cached file has been modified, communicating the cached file to the database. In one embodiment of the present invention, the software program can determine if the cached file has been modified through automatic notification from a file management system. Alternatively, the software program can poll a cached file to determine if the cached file has changed. In another embodiment of the present invention, the software program can be further executable to perform the step of prompting an operating system to open the cached file in an application associated with the cached file&#39;s file type. In another embodiment of the present invention, the software program can be further executable to receive notifications from a database of when contention for a database asset occurs. Thus, bi-directional synchronization can occur. 
     Embodiments of the present invention provide a technical advantage because they do not require a user to manually save changes in a separate synchronization program, thereby saving substantial time and reducing latency. 
     Another technical advantage of the embodiments of the method and system of the present invention is the ability to synchronize cached files corresponding to a multitude of file types. Because various embodiments of the present invention can synchronize cached files, regardless of the file type, a user can employ his or her preferred tools of choice and he or she will not have to rely on unfamiliar, custom designed applications. 
     Yet another technical advantage of embodiments of the present invention is the capability to seamlessly synchronize a cache with a database. Because embodiments of the present invention can automatically determine if a cached file has been modified and can communicate the cached file to the database, latency is substantially reduced. 
     Embodiments of the present invention provide yet another technical advantage by being compatible with a variety of database and network architectures. 
     Still another technical advantage provided by embodiments of the present invention is the ability to reestablish database connections, thus increasing the likelihood that synchronization will occur. 
     Embodiments of the present invention provide yet another technical advantage by having the capability to receive notifications from the database when contention for a database asset occurs. Because a user can be made aware of when another user attempts to access the same database asset, issues of contention can be resolved more efficiently. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A more complete understanding of the present invention and the advantages thereof may be acquired by referring to the following description, taken in conjunction with the accompanying drawings in which like reference numbers indicate like features and wherein: 
         FIG. 1  illustrates a network that can include a client computer utilizing a cache manager according to an embodiment the present invention; and 
         FIG. 2  is a flow chart diagramming the operation of one embodiment of the method and system for synchronization of a cache according to the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Preferred embodiments of the present invention are illustrated in the FIGUREs, like numerals being used to refer to like and corresponding parts of the various drawings. 
     The embodiments of the method and system of the present invention provide the capability to seamlessly and transparently access database files locally and synchronize cached files with a database. Embodiments of the present invention provide the ability to save a database asset as a local cached file, determine if the cached filed has been accessed or modified, and if the cached file has been accessed or modified, synchronize the cached file and the associated database (e.g., the database from which the database asset was received). Additionally, the embodiments of the present invention can also provide the ability to open, view, and/or modify database assets via a user&#39;s preferred application or software tool. 
       FIG. 1  illustrates a system  20  that can include a client computer  22  utilizing a cache manager  38  for managing a cache  40  according to one embodiment of the present invention. System  20  can include at least one client computer  22  and at least one server computer  24  (“Server  24 ”). Client computer  22  can connect to server  24  via a network  26 . Network  26  can comprise any global computer network (e.g., the Internet), a wireless network, a local area network, or any other network capable of transporting data between a client computer and a server. Client computer  22  can be a personal computer, a workstation, a wireless device, a laptop computer, or any other computer device operable to access data from a database. Client computer  22  can include a central processing unit (CPU)  30  connected to a computer-readable memory  32 . Memory  32  can comprise any combination of RAM, ROM, magnetic storage device, such as a hard drive, and/or other computer readable memory known in the art. Furthermore, while in  FIG. 1  memory  32  is shown to be connected locally to CPU  30  at client computer  22 , memory  32  can be distributed between several devices. 
     Memory  32  can store a number of computer programs, including an operating system  34 , various applications  36  (that can comprise software tools) that can include word processing tools or other software tools known to those in the art, and a cache manager  38  residing in user-space. The concept of user-space is well-known to those of ordinary skill in the art. Operating system  34  can further include a file management system  35  to organize and keep track of files in memory  32 . Memory  32  can also include a cache  40  which can contain cached versions of database assets, such as cached file  42 . As will be discussed in greater detail below, cached file  42  can be a cached version, either modified or unmodified, of database asset  43 . Client computer  22  can establish network communication through a network connection device  44 . Network connection device  44  can be any network communication device that is known to those in the art. 
     Server  24  can include standard server computer components, including a server network connection device  46 , a CPU  48 , and a memory (primary and/or secondary)  50 . Network connection device  46 , CPU  48 , and memory  50  can be equivalent components to network connection device  44 , CPU  30 , and memory  32  of client computer  22 . Memory  50  can store database management program  52 , which can be executable to carry out standard database functions, including receiving requests for data, retrieving the data, and returning the data to the requesting computer. Memory  50  can also include a database  54 , which can include various database assets, such as database asset  43 . The database assets can include a variety of different file types, including, but not limited to, text files, spreadsheet files, graphics files, html files, etc. 
     It should be noted that the system architecture illustrated in  FIG. 1  is by way of explanation only and is designed to give context to the embodiments of the present invention. However, various embodiments of cache manager  38  can be implemented with different architectures of client computer  22  and/or server computer  24 . 
     In operation, a user wishing to access database assets (e.g., database asset  43 ) can establish a connection through a standard network application, as is known to those in the art, with a server (e.g., server  24 ) associated with the database (e.g., database  54 ) on which the particular database asset (e.g., database asset  43 ) is stored. Cache manager  38  can be executable by CPU  30  to establish a connection with server  24  in any manner known in the art of establishing database connections through network connection device  44 . As is understood by those with ordinary skill in the art, access to a database typically requires authentication with the database. Therefore, the user, when initially attempting to access server  24  (and database  54  associated therewith) may be required to enter login and authentication information. As will be discussed in greater detail below, in one embodiment of the present invention, cache manager  38  can store the login and authentication information so that if the connection to server  24  is subsequently dropped or lost, cache manager  38  can re-establish the connection without requiring the user to re-enter his/her login and/or authentication information. 
     Once the user has established a connection to server  24 , cache manager  38  can determine the contents of database  54  and can enumerate the contents for display by a program in, for example, a graphical user interface. In one embodiment of the present invention, cache manager  38  can interface with file management system  35  for display of the database assets in a pre-existing interface. In a hierarchical file management system  35 , for example, file management system  35  will use directories to organize files into a tree structure. Thus, in the case of a hierarchical file management system  35 , cache manager  38  can interface with the hierarchical file management system  35  of operating system  34  to display database  54  as an additional tree node in the directory display and to organize database assets into the tree structure under the database directory. In the well-known Microsoft™ Windows operating system, database  54  could appear as an additional drive in a directory tree of the Windows Explorer display, and each database asset could appear as a file under the database directory. Alternatively, rather than interfacing with file management system  35 , cache manager  38  can provide an independent and/or custom graphical user interface for organizing representations of database assets. 
     The user can select a database asset in which he/she is interested from the graphical user interface used by cache manager  38  (e.g., either the independent graphical user interface or the graphical user interface integrated with file management system  35 ). When the user selects a database asset (e.g., database asset  43 ) by, for example, double clicking on the database asset in the Windows™ Explorer display, cache manager  38  can determine if the connection to server  24  is still established. If the connection has been lost, cache manager  38  can establish a connection to server  24 . If the connection is still established, (or once the connection is re-established), cache manager  38  can request the selected database asset (e.g., database asset  43 ). Database management program  52  will receive the request and search database  54  for database asset  43 , retrieve database asset  43 , and communicate a copy of database asset  43  to client computer  22  while typically maintaining a copy of database asset  43  on database  54 . Cache manager  38  can receive database asset  43  and store database asset  43  as cached file  42  on memory  32 . In addition, cache manager  38  can associate cached file  42  with a particular connection (e.g., with a particular database) so that if the user is accessing multiple databases, cache manager  38  can keep track of the database from which a cached file was retrieved. Cache manager  38  can also associate cached file  42  with a unique location on memory  32 . In other words, cache manager  38  can store cached file  42  in a unique location in the file system of file management system  35 . 
     Assume, for example, that database asset  43  is the file “myfile.jpg”. When the user requests myfile.jpg, cache manager  38  can request the file from server  24 . Database management program  52  can search database  54  for myfile.jpg, retrieve myfile.jpg, and send a copy of myfile.jpg to client computer  22  while retaining a copy on database  54 . Cache manager  38  can receive myfile.jpg and associate myfile.jpg with database  54 . Cache manager  38  can also save myfile.jpg as cached file  42  in cache  40  of memory  32  and associate myfile.jpg with a unique location in memory  32 . As an example, cache manager  38  could store myfile.jpg on a hard disk drive (e.g., in memory  32 ) as “C:\cache\db54\myfile.jpg.” 
     Operating system  34  can then open cached file  42  with whichever application  36  is associated with the file type for cached file  42 . For example, if cached file  42  was myfile.jpg and operating system  34  normally opened .jpg files with Adobe™ Photoshop (“PhotoShop”) (e.g., assume PhotoShop was associated with the .jpg file format), operating system  34  would open myfile.jpg with PhotoShop. The user is then free to view or modify myfile.jpg (e.g., cached file  42 ) in PhotoShop (e.g., application  36 ). As files can be opened with the application or software programs that are associated with the particular file type, a user can utilize his/her preferred tool of choice to work on a file just as if (s)he were working from a file directly from file management system  35 , providing a significant advantage over prior art systems. 
     After viewing and/or modifying myfile.jpg, the user can again save the file. When the user saves cached file  42  (e.g., when the user saves myfile.jpg in PhotoShop), cached file  42  can be saved in cache  40  of memory  32  at the location previously associated with cached file  42  by cache manager  38 . In other words, application  36  will save cached file  42  back to the location from which application  36  opened cached file  42 . In the case of myfile.jpg, this could entail saving myfile.jpg back to “C:\cache\db54\myfile.jpg.” 
     In one embodiment of the present invention, cache manager  38  can interface with file management system  35  of operating system  34  to receive notification of when a particular file (e.g., cached file  42 ) has been saved by the user. For example, when a user saves a change to myfile.jpg, file management system  35  can notify cache manager  38  that cached file  42  has been saved. Thus, if file management system  35  supports automatic notification, cache manager  38  can exploit an inherent feature of file management system  35  to determine when cached file  42  is saved. It should be noted, however, that while the file management system  35  of the Microsoft™ Windows operating system allows for notification of when a file has changed, not all operating systems do so. If file management system  35  does not support automatic notification of when files are saved, cache manager  38  can poll cached file  42  to determine if cached file  42  has been modified. One method of polling files is disclosed in U.S. patent application Ser. No. 10/034,712, entitled “Method and System for Optimizing Resources for Cache Management”, filed on Dec. 18, 2001, to inventors David Thomas and Scott Wells (the “Management Application”), which is hereby fully incorporated by reference. 
     Upon determining that cached file  42  has been saved, cache manager  38  can determine with which connection (e.g., with which database) cached file  42  is associated. In the continuing example of myfile.jpg, since myfile.jpg was received from database  54 , myfile.jpg is associated with database  54 , as described earlier. If the connection with which cached file  42  is associated has been dropped or lost, cache manager  38  can, in one embodiment of the present invention, re-establish the connection. This can be done by using the previously stored login and authentication information or by prompting the user to re-enter the login and/or authentication information. If the connection was not dropped or when the connection is re-established, cache manager  38  can communicate a copy of cached file  42  directly (e.g., without the use of an intermediate synchronization program) to server  24 . Because cache manager  38  can re-establish lost or dropped connections, the user can still save files back to database  54  following a dropped connection. 
     If, after several attempts, cache manager  38  cannot re-establish the connection, cache manager  38  can notify the user that the connection has been lost and give the user the opportunity to backup cached file  42 . Additionally cache manager  38  can delete cached file  42  so that cache  40  does not contain cached files that cannot be synchronized with a database because the connection associated with cached file  42  has been dropped. 
     It should be noted that even after cache manager  38  has communicated cached file  42  to server  24 , a copy of cached file  42  can remain on memory  32  of client computer  22  so that the user can continue to work on cached file  42 . Whenever cache manager  38  determines that cached file  42  has again been saved or closed in application  36 , either through notification from file management system  35  or through polling, cache manager  38  can again communicate cached file  42  to server  24 . Database management software  52  can then save cached file  42  as database asset  43 , thus synchronizing database  54  with cached filed  42 . 
     As can be understood from the foregoing discussion, the present invention can provide substantial advantages over previously developed systems for managing database assets. Because cache manager  38  can run in the background, a user&#39;s access to and modification of database assets can occur essentially transparently. Furthermore, because embodiments of cache manager  38  can interface with file management system  35  to receive notifications of when changes occur to cached file  42 , cache manager  38  can quickly communicate the saved changes or modifications to database  54 , thus reducing the latency between when cached file  42  is modified and when corresponding database asset  43  is updated. Also, because cache manager  38  can determine when cached file  42  has been saved, the user does not have to save cached file  42  in a separate synchronization program. Furthermore, as cache manager  38  can reside in user-space, cache manager  38  is much less likely to de-stabilize client computer  22 , as would an operating system level program. Also, cache manager  38  can be transparent to the tools or applications used to access modify cached files. 
       FIG. 1  illustrates a system in which there is one client computer  22  and one server  24 . However, it should be noted that there may be many client computers  22  and many servers  24 . Potentially, a single user could access multiple databases and several users could access the same database. Because many users may be attempting to access the same database, contention for the same database asset can occur. For example, while a first user is working on database asset  43  (e.g., is modifying cached file  42 ) on his/her client computer  22 , a second user could attempt to access database asset  43  from database  54 . In one embodiment of the present invention, cache manager  38  can receive notifications from database management program  52  of when additional users access database asset  43 . Cache manager  38  can then present, in a graphical user interface, various choices to the user as to how to resolve the contention over database asset  43 . For example, the first user could be given, in a dialog box, the choice to retrieve the latest version of database asset  43  with any changes made by the second user. Alternatively, database management program  52  could implement automatic rules such as giving priority to the first user, etc. 
     In addition to receiving notifications from database management program  52  regarding database assets upon which a user is currently working, cache manager  38  can receive notifications regarding database assets upon which the user has previously worked (e.g., database assets for which there is a corresponding cached file  42  in cache  40 ). Thus, for example, if a user has previously worked on database asset  43  and a version of cached file  42  remains in cache  40 , cache manager  38  can receive notifications regarding database asset  43 . If database asset  43  were changed by another user, cache manager  38  can receive a notification from database management program  52  regarding the change and present the notification to the user (e.g., in a graphical user interface such as a dialog box). Thus, cache manager  38  can receive information regarding various database assets (e.g., database asset  43 ) upon which a user has worked. It should be noted that database management programs  52  that provide such notifications are well known in the art. 
     Cache manager  38  can also receive notifications from database management system  52  that a database asset for which there is a corresponding cached file  42  in cache  40  has been deleted from database  54 . In one embodiment of the present invention, upon receipt of such notification, cache manager  38  can notify the user via a graphical user interface that the database asset has been removed and can purge the corresponding cached file  42  from cache  40 . 
     By having the capability to seamlessly save changes to a cached file to a database and receive notifications from the database management program regarding the associated database asset, cache manager  38  can participate in bi-directional synchronization of the cache. That is, cache manager  38  can synchronize database asset  43  with cached file  42  whenever changes are made (or detected via polling) to cached file  42 , and cache manager  38  can notify a user of changes made by others to database asset  43 . Thus, database asset  43  can reflect the most recent changes made by a user to cached file  42  and users can be made aware of changes made by others to database asset  43 . 
       FIG. 2  is a flow chart diagramming the operation of one embodiment of the method and system for cache synchronization of this invention. At step  60 , cache manager  38  can receive a request to establish a connection to database  54 . The request can occur, for example, in response to an employee attempting to connect to a corporate database. Cache manager  38  can establish a connection to a server associated with database  54  (e.g., server  24 ), at step  62 , via standard network communication device  44 . As would be understood by those of ordinary skill in the art, access to a database often requires that a user enter a login and/or other authentication information. To prevent the user from having to re-enter this information if the connection to server  24  is dropped or lost, cache manager  38 , at step  63 , can save the login or authentication information. Cache manager  38 , at step  64 , can provide the contents of the database (e.g., database  54 ) to an external graphical user interface. In one embodiment of the present invention, the graphical user interface can be integrated into an interface provided by file management system  35  of operating system  34 . Thus, in a Microsoft® Windows environment, database  54  could appear as an additional tree node in a directory display in the Windows Explorer file management system and each database asset associated with database  54  can appear as a file in the file tree display of the Windows® Explorer display. In an alternative embodiment of the present invention, cache manager  38 , at step  64 , can display the database contents in an independent graphical user interface. This can be done in systems where integration with operating system  34  and its associated file management system  35  cannot be easily achieved. 
     Based on the database assets displayed in the graphical user interface, the user can select the database asset with which he/she wishes to work (e.g., database asset  43 ). This can be done in a Windows-based environment, for example, by the user double clicking on the database asset displayed in the Windows Explorer display. At step  68 , cache manager  38  can receive a request for the selected database asset. Cache manager  38  can then determine, at step  70 , if the connection to the database with which the database asset is associated (e.g., database  54 ) is still present or whether it has been dropped or disconnected. If the connection has been dropped or disconnected, cache manager  38 , at step  71 , can re-establish the connection using either re-entered login and/or authentication information from the user or login and/or authentication information that was saved at step  63 . After the connection is re-established, or if the connection was not dropped or disconnected as determined at step  70 , cache manager  38 , at step  72 , can make a request to server  24  for the selected database asset. 
     At server  24 , database management program  52  can receive the request for the selected database asset (e.g., database asset  43 ), search database  54  for the database asset, and, if the database asset is found, communicate the database asset to client computer  22 . At step  76 , cache manager  38  can receive a copy of the database asset and save the copy of the database asset as cached file  42  in cache  40  of memory  32 . Additionally, at step  78 , cache manager  38  can associate the cached file  42  with a particular connection. Because cached files are associated with a particular connection, cache manager  38  will be able to communicate changes associated with a database asset (e.g., changes to the corresponding cache file) back to the appropriate (e.g., the associated) database. Cache manager  38 , at step  80 , can also associate cached file  42  with a unique location in memory  32  (e.g., at cache  40  of client computer  22 ). Thus, for example, if database asset  43  was the file myfile.jpg, cache manager  38  can save database asset  43  as cached file  42  at the location “C:\cache\db54\myfile.jpg.” 
     Cache manager  38 , at step  82 , can prompt operating system  34  to open cached file  42  (e.g., myfile.jpg). Operating system  34  can open cached file  42  with the application  36  with which operating system  34  (or the user) would normally open such a file. Thus, for example, if .jpg files were associated with PhotoShop, operating system  34  can open myfile.jpg with PhotoShop (e.g., application  36 ) from “C:\cache\db54\myfile.jpg.” The user can then view and/or modify cached file  42  (e.g., myfile.jpg) in the appropriate application  36  (e.g., PhotoShop). 
     In order to synchronize database asset  43  with cached file  42 , cache manager  38 , at step  84 , can determine if the cached file  42  has been modified. As described earlier, this can be done either through receiving notification from file management system  35  that cached file  42  has been saved or by polling cached file  42  to determine if the file has changed. As described in the Management Application, polling can be done, for example, by reading a time stamp associated with cached file  42  to determine the last time at which cached file  42  was modified. If the time stamp from the most recent polling of cached file  42  does not match the time stamp from a previous polling of cached file  42 , then cached file  42  has been modified and cache manager  38  can attempt to synchronize cached file  42  with database  54 . As can be understood by those of ordinary skill in the art, the frequency at which cache manager  38  polls cached file  42  can be adjusted to optimize the resources of client computer  22 . A more frequent polling will require more resources but will result in a lower latency between the time when a cached file  42  is modified and when cache manager  38  determines cached file  42  has been modified. Conversely, a longer time interval between each polling of cached file  42  will reduce the required resources of client computer  22  but can lead to a longer latency period. Thus, the polling interval can be set to optimize system resources with respect to latency period. 
     Returning now to  FIG. 2 , if at step  84  cache manager  38  determines that cached file  42  has not been modified (e.g., changed, deleted, etc.), cache manager  38  can continue to either poll cached file  42  for modifications or wait for file management system  35  to indicate that cached file  42  has been modified. If, on the other hand, cache manager  38  determines at step  84  that cached file  42  has been modified (e.g., through polling or notification from file management system  35 ), cache manager  38  can determine, at step  86 , if the connection associated with cached file  42  (e.g., the connection to database  54  over which cache manager  38  received database asset  43 ) is still established. If the connection has been dropped, cache manager  38  can re-establish the connection at step  88 . If login or authentication information is required to re-establish the connection, cache manager  38  can use the login or authentication information saved from the user at step  63  or, alternatively, prompt the user to enter new login and/or authentication information. Once the connection has been re-established at step  88  (or, if at step  86  cache manager  38  determined that the connection associated with cached file  42  was still established), cache manager  38 , at step  90 , can save a copy of cached file  42  directly to database  54  (e.g., without the need for an intermediate synchronization program). Cached file  42  can then be saved as database asset  43 , and thus, database  54  can be synchronized with the most recent changes made to cached file  42 . At step  92 , cache manager  38  can optionally repeat steps  84 - 90  for cached file  42  until the user ceases work on cached file  42  or, alternatively, cached file  42  expires (some pre-determined amount of time passes during which cached file  42  is not viewed or modified). 
     Because cached file  42  can be communicated to database  54  immediately or almost immediately after cached file  42  has been modified, database asset  43  can more accurately reflect the latest revisions to database asset  43 . Thus, subsequent users accessing database asset  43  are ensured of having the latest revisions to database asset  43 . Furthermore, because cache manager  38  can use inherent notification features of file management system  35  or can automatically poll cached file  42  for changes, the present invention does not require the user to save cached file  42  to database  54  using a separate synchronization program, thereby further reducing latency. Additionally, by omitting the extra step of saving cached file  42  in a synchronization program, the user can save time each time he/she modifies a cached file. 
     The teachings of the present invention provide an additional advantage by enabling the “seamless” use of tools of choice. Because cache manager  38  can prompt operating system  34  to open cached file  42  in the application  36  with which the file type of cached file  42  is normally associated, users can use their tools of choice to modify and view database assets without having to rely on custom designed and unfamiliar tools provided by database vendors or on being limited to using only those tools for which a synchronization program exists. Additionally, because cache manager  38  resides at the file system level rather than at the operating system level (e.g., resides in user space, rather than operating space), cache manager  38  is less likely to degrade the stability of client computer  22 . 
     In addition to reducing latency, empowering tools of choice, and maintaining stability of client computer  22 , cache manager  38  can help resolve contention between various users for the same database asset. As can be understood by those of ordinary skill in the art, embodiments of database management software program  52  can send notification of when a user attempts to access a database asset. For example, database management software program  52  could send a notification to cache manager  38  when an additional user attempts to access a database asset  43 . Cache manager  38  can then send a notification to the first user, via a graphical user interface, that another user is attempting to access database asset  43 . In one embodiment of the present invention, this can occur whether or not the first user is currently working on cached file  42 . The first user can be given various options, such as to view the latest version of database asset  43  or, if the first user is currently modifying cached file  42 , overriding changes made by any other user to database asset  43 . 
     Because cache manager  38  can be notified when other users attempt to modify database asset  43 , each user who has previously accessed and modified database asset  43  can be made aware of changes to that database asset. Thus, if several members of a team are working on a project involving database asset  43 , each member can be made aware of when another member of the team (or some other user) modifies or accesses database asset  43 , thereby aiding in control of the database asset. Furthermore, cache manager  38  can provide bi-directional synchronization of database asset  43  by not only saving changes made to cached file  42  to database  54 , but also by notifying users of changes in database asset  43 . 
     As can be understood from the foregoing discussion, embodiments of the present invention provide a system for seamlessly and transparently synchronizing database assets as users work on those assets. Embodiments of the present invention also provide the advantage of allowing users to employ tools of choice without having to perform the extra steps required for saving a database asset through a separate synchronization program. Additionally, the teachings of the present invention enable the use of tools of choice regardless of a database asset&#39;s file type. Further, embodiments of the present invention are less likely to degrade the stability of client computer  22 . 
     Although the present invention has been described in detail herein with reference to the illustrative embodiments, it should be understood that the description is by way of example only and is not to be construed in a limiting sense. It is to be further understood, therefore, that numerous changes in the details of the embodiments of this invention and additional embodiments of this invention will be apparent to, and may be made by, persons of ordinary skill in the art having reference to this description. It is contemplated that all such changes and additional embodiments are within the spirit and true scope of this invention as claimed below.

Technology Classification (CPC): 6