What Is The Full Form Of XSD?
The full form of XSD is XML Schema Definition.
XSD is a way to formally describe the structure and elements in an XML (Extensible Markup Language) document. The purpose of XSD is to define the legal building blocks that relate to an XML document. It determines every rule for a document’s attributes, and it checks the vocabulary as well. Programmers use XSD to verify all the pieces of content in an XML doc to ensure that they adhere to the description of the elements in which they place them. One can use XSD to express the set of rules to which an XML doc must conform for being considered valid according to the schema.
History of XSD
- XML Schema was published as a recommendation from W3C (World Wide Web Consortium) in May 2001.
- Out of all the schema languages, it was the first separate one for XML- that got a recommendation status from the W3C.
- Since the term described XML languages, a part of the user community started referring to the W3C recommended XML Schema as WXS, while others referred to it as XSD.
- W3C chose to adopt XSD in version 1.1 as the preferred name.
- The original XSD 1.0 specification was published in 2001.
- The second edition followed in 2004, and it corrected a large number of errors.
Characteristics of XSD
- XSD describes an XML document’s structure.
- It supports namespaces, and it is extensible for the additional features.
- XSD supports different types of data.
- The W3C organization supports XSD for XML docs.
- XSD defines the legal building blocks of a document. They include the attributes and elements of the doc, the data types, default and fixed values, and the number and order of every element.
- Various standardized XML formats come into play every day, and XSD is a powerful alternative compared to the DTD.
Features of XSD
- XSD makes it easier for a user to identify and define the data patterns.
- They bring extra security over data communication.
- XSD requires no processing by a parser.
- It checks and updates the correctness of a file.
- XSDs can be extended correctly for further additions in the future.
Benefits of XSD
- XSD can provide a restriction on any data.
- It is extensible- meaning you can feasibly derive new elements from the existing ones. DTD, on the other hand, is not extensible.
- XSD supports the default values. So you can specify the default values of the elements involved.
- It supports all data types, and you can restrict the content of an element.
- XSD is defined in XML and thus requires no intermediate processing by a parser.
- XSD also supports the reference to external XSD schemas. And you can include/ import more XML schemas within a single XML schema.
Limitations of XSD
- XSD is too complicated and very complex in its nature.
- It has weak and insufficient support for unordered content.
- It has no formal mathematical description.
- XSD has limited documentation support overall.
- It is not 100% self-describing, and complications may arise due to it.
- The two tasks of augmentation and validation (default values and adding type information) should be kept separate.