If your schemas are large, you might choose to divide their
content among several schema documents to make them easier to maintain,
reuse, and read. You can use the include element
to bring in definitions and declarations from the included schema
into the current schema. The included schema must be in the same target
namespace as the including schema.
The following instructions were written for the Resource
perspective, but they will also work in many other perspectives.
To
add an include element, complete the following steps:
Once you have added the include element to your XML schema,
when you define new elements, attributes, complex types, or simple
types where you can specify type information, any declarations from
the included schema will be available in the Type list
for the element, attribute, complex or simple type.
For example,
if Address.xsd has the following content:
<complexType name="Address">
<sequence>
<element name="name" type="string">
<element name="street" type="string">
</sequence>
</complexType>
and you have an XML schema called PurchaseOrder.xsd that
has added an include for Address.xsd, then when defining a new element
in PurchaseOrder, you can select Address as its type.