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Data Format Description Language (DFDL, often pronounced ''daff-o-dil''), published as an Open Grid Forum Proposed Recommendation in January 2011, is a modeling language for describing general text and binary data in a standard way. A DFDL model or schema allows any text or binary data to be read (or "parsed") from its native format and to be presented as an instance of an ''information set''. (An information set is a logical representation of the data contents, independent of the physical format. For example, two records could be in different formats, because one has fixed-length fields and the other uses delimiters, but they could contain the exact same data, and would both be represented by the same information set). The same DFDL schema also allows data to be taken from an instance of an information set and written out (or "serialized") to its native format. DFDL is ''descriptive'' and not ''prescriptive''. DFDL is not a data format, nor does it impose the use of any particular data format. Instead it provides a standard way of describing many different kinds of data format. This approach has several advantages.〔(The Syntax of Data, Mike Beckerle blog )〕 It allows an application author to design an appropriate data representation according to their requirements while describing it in a standard way which can be shared, enabling multiple programs to directly interchange the data. DFDL achieves this by building upon the facilities of W3C XML Schema 1.0. A subset of XML Schema is used, enough to enable the modeling of non-XML data. The motivations for this approach are to avoid inventing a completely new schema language, and to make it easy to convert general text and binary data, via a DFDL information set, into a corresponding XML document. Educational material is available in the form of a DFDL Tutorial, videos and several hands-on DFDL labs. ==History== DFDL was created in response to a need for grid APIs to be able to understand data regardless of source. A language was needed capable of modeling a wide variety of existing text and binary data formats. A (working group ) was established at the Global Grid Forum (which later became the Open Grid Forum) in 2003 to create a specification for such a language. A decision was made early on to base the language on a subset of W3C XML Schema, using Work continued on the language, resulting in the publication of a DFDL 1.0 specification as OGF Proposed Recommendation GFD.174 in January 2011. The latest revision is (GFD.207 ) published in November 2014 which obsoletes GFD.174 and incorporates all issues noted to date (also available as (html )). A (summary ) of DFDL and its features is available at the OGF. Any issues with the specification are being tracked using (Redmine issue trackers ). 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「Data Format Description Language」の詳細全文を読む スポンサード リンク
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