15.2.25. XML Schema reference manual

发布时间 :2025-10-25 12:23:26 UTC      

XSD element

element

explain

all

It is stipulated that child elements can appear in any order, and each child element can appear zero or once.

annotation

The annotation element is a top-level element that specifies the comments for the schema.

any

Enables creators to extend schema documents through elements that are not specified by XML.

anyAttribute

Enables creators to extend schema documents with attributes that are not specified by XML.

appInfo

Specifies the information that the application will use in the annotation element.

attribute

Define an attribute.

attributeGroup

Defines the property groups used in complex type definitions.

choice

Only one element in the < choice > declaration is allowed to appear in the containing element.

complexContent

Defines extensions or restrictions on complex types that contain mixed content or only elements.

complexType

Define complex types.

documentation

Define text comments in schema.

element

Define the element.

extension

Extend existing simpleType or complexType elements.

field

Specifies the XPath expression that specifies the value used to define the identity constraint.

group

Defines the group of elements used in a complex type definition.

import

Add multiple schema with different target namespaces to a document.

include

Add multiple schema with the same target namespace to a document.

key

The specified attribute or element value (or set of values) must be a key within the specified range.

keyref

Specifies that the value of an attribute or element (or set of values) corresponds to the value of the specified key or unique element.

list

Defines a simple type as a list of values of the specified data type.

notation

Describes the format of non-XML data in an XML document.

redefine

Redefine simple and complex types, groups, and property groups obtained from external schema files.

restriction

Define constraints on simpleType, simpleContent, or complexContent.

schema

Define the root element of the schema.

selector

Specifies the XPath expression that selects a set of elements for the identity constraint.

sequence

Requires that child elements appear in order. Each child element can appear from 0 to any number of times.

simpleContent

Contains extensions or restrictions on complexType elements and does not contain any elements.

simpleType

Define a simple type that specifies constraints and information about the value of an attribute or text-only element.

union

Defines a collection of multiple simpleType definitions.

unique

Specifies that an attribute or element value (or a combination of attribute or element values) must be unique within the specified range.

XSD qualification / Facets

参阅 XSD 限定 / Facets

Limit

Description

Enumeration

Define a list of acceptable values

FractionDigits

Defines the maximum number of decimal places allowed. Must be greater than or equal to 0.

Length

Defines the exact number of characters or list items allowed. Must be greater than or equal to 0.

MaxExclusive

Defines the upper limit of the value. The allowed value must be less than this value.

MaxInclusive

Defines the upper limit of the value. The allowed value must be less than or equal to this value.

MaxLength

Defines the maximum number of characters or list items allowed. Must be greater than or equal to 0.

MinExclusive

Defines the lower limit of the value. The allowed value must be greater than this value.

MinInclusive

Defines the lower limit of the value. The allowed value must be greater than or equal to this value.

MinLength

Defines the minimum number of characters or list items allowed. Must be greater than or equal to 0.

Pattern

Defines a precise sequence of acceptable characters.

TotalDigits

Defines the exact number of digits allowed for Arabic numerals. Must be greater than 0.

WhiteSpace

Defines how white space characters (line feeds, carriage returns, spaces, and tabs) are handled.

Principles, Technologies, and Methods of Geographic Information Systems  102

In recent years, Geographic Information Systems (GIS) have undergone rapid development in both theoretical and practical dimensions. GIS has been widely applied for modeling and decision-making support across various fields such as urban management, regional planning, and environmental remediation, establishing geographic information as a vital component of the information era. The introduction of the “Digital Earth” concept has further accelerated the advancement of GIS, which serves as its technical foundation. Concurrently, scholars have been dedicated to theoretical research in areas like spatial cognition, spatial data uncertainty, and the formalization of spatial relationships. This reflects the dual nature of GIS as both an applied technology and an academic discipline, with the two aspects forming a mutually reinforcing cycle of progress.