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WinFS (short for Windows Future Storage) is the code name for a canceled data storage and management system project based on relational databases, developed by Microsoft and first demonstrated in 2003 as an advanced storage subsystem for the Microsoft Windows operating system, designed for persistence and management of structured, semi-structured as well as unstructured data. WinFS includes a relational database for storage of information, and allows any type of information to be stored in it, provided there is a well defined schema for the type. Individual data items could then be related together by relationships, which are either inferred by the system based on certain attributes or explicitly stated by the user. As the data has a well defined schema, any application can reuse the data; and using the relationships, related data can be effectively organized as well as retrieved. Because the system knows the structure and intent of the information, it can be used to make complex queries that enable advanced searching through the data and aggregating various data items by exploiting the relationships between them. While WinFS and its shared type schema make it possible for an application to recognize the different data types, the application still has to be coded to render the different data types. Consequently, it would not allow development of a single application that can view or edit all data types; rather what WinFS enables applications to understand is the structure of all data and extract the information that it can use further. When WinFS was introduced at the 2003 Professional Developers Conference, Microsoft also released a video presentation, named IWish,〔(【引用サイトリンク】 IWish Concept Video )〕 showing mockup interfaces that showed how applications would expose interfaces that take advantage of a unified type system. The concepts shown in the video ranged from applications using the relationships of items to dynamically offer filtering options to applications grouping multiple related data types and rendering them in a unified presentation. WinFS was billed as one of the pillars of the "Longhorn" wave of technologies, and would ship as part of the next version of Windows. It was subsequently decided that WinFS would ship after the release of Windows Vista, but those plans were shelved in June 2006, with some of its component technologies being integrated into upcoming releases of ADO.NET and Microsoft SQL Server. While it was then assumed by observers that WinFS was finished as a project, in November 2006 Steve Ballmer announced that WinFS was still in development, though it was not clear how the technology was to be delivered. Several components of the last Integrated Storage Initiative project, Microsoft Semantic Engine, presented at Microsoft PDC 2009, have been integrated back into the SQL Server "Denali". At the 2010 SQL Server PASS Community Summit, the forthcoming version of SQL Server ("Denali") was shown, which seems to incorporate many of the WinFS ideas. ==Motivation== Many filesystems found on common operating systems, including the NTFS filesystem which is used in modern versions of Microsoft Windows, store files and other objects only as a stream of bytes, and have little or no information about the data stored in the files. Such file systems also provide only a single way of organizing the files, namely via directories and file names. Because a file system has no knowledge about the data it stores,〔 applications tend to use their own, often proprietary, file formats. This hampers sharing of data between multiple applications. It becomes difficult to create an application which processes information from multiple file types, because the programmers have to understand the structure and semantics of all the files. Using common file formats is a workaround to this problem but not a universal solution; there is no guarantee that all applications will use the format. Data with standardized schema, such as XML documents and relational data fare better, as they have a standardized structure and run-time requirements. Also, a traditional file system can retrieve and search data based only on the filename, because the only knowledge it has about the data is the name of the files that store the data.〔 A better solution is to tag files with attributes that describe them. Attributes are metadata about the files such as the type of file (such as ''document'', ''picture'', ''music'', ''creator'', etc.).〔 This allows files to be searched for by their attributes, in ways not possible using a folder hierarchy, such as finding ''"pictures which have person X"''. The attributes can be recognizable by either the file system natively, or via some extension.〔 Desktop search applications take this concept a step further. They extract data, including attributes, from files and index it. To extract the data, they use a filter for each file format. This allows for searching based on both the file's attributes and the data in it.〔 However, this still does not help in managing related data, as disparate items do not have any relationships defined. For example, it is impossible to search for ''"the phone numbers of all persons who live in Acapulco and each have more than 100 appearances in my photo collection and with whom I have had e-mail within last month"''. Such a search could not be done unless it is based on a data model which has both the semantics as well as relationships of data defined.〔〔 WinFS aims to provide such a data model and the runtime infrastructure that can be used to store the data, as well as the relationships between data items according to the data model, doing so at a satisfactory level of performance. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「WinFS」の詳細全文を読む スポンサード リンク
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