XML Schema is a file that defines the content used in an XML document.

XML Schema provides data typing, which enables defining data by type (character, integer). Schema reuse, or schema inheritance, enables tags referenced in one schema to be used in other schemas. XML Schema name spaces enable multiple schemas to be combined into one. Global attributes within XML Schema assign properties to all elements. XML Schema also allows associating Java classes for additional data processing. Authoring information adds improved documentation for schema designers.

Unlike DTD files, XML schemas are written in XML syntax. Although more verbose than DTD files, XML Schemas can be created with any XML tools. Examples of XML schemas can be found at www.xml.org.

In XML Schema, there is a basic difference between complex types, which allow elements in their content and may carry attributes, and simple types, which cannot have element content and cannot carry attributes. There is also a major distinction between definitions that create new types (both simple and complex), and declarations that enable the appearance in document instances of elements or attributes with specific names and types (both simple and complex).

The following simple types are currently supported for XML Schema connections:

Within XML Schema, new simple types are defined by derivation from existing simple types (built-in's and derived) through a technique called restriction. A new type must have a name different from the existing type, and the new type may constrain the legal range of values obtained from the existing type by applying one or more facets.

XML Schema simple types are supported to the extent that we recognize them and will use a type with that name. But the integration platform has no way to handle many of the simple types, such as timePeriod and century, so they will use that type in name only within your transformations.