newsupernova/vendor/magento/module-eav/etc/eav_attributes.xsd

<?xml version="1.0" encoding="UTF-8"?>
<!--
/**
 * Copyright © Magento, Inc. All rights reserved.
 * See COPYING.txt for license details.
 */
-->
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
    <xs:element name="config">
        <xs:complexType>
            <xs:sequence>
                <xs:element name="entity" type="entityDeclaration" minOccurs="1" maxOccurs="unbounded">
                    <xs:unique name="uniqueAttributeCode">
                        <xs:annotation>
                            <xs:documentation>
                                Attribute code must be unique
                            </xs:documentation>
                        </xs:annotation>
                        <xs:selector xpath="attribute" />
                        <xs:field xpath="@code" />
                    </xs:unique>
                </xs:element>
            </xs:sequence>
        </xs:complexType>
        <xs:unique name="uniqueEntityType">
            <xs:annotation>
                <xs:documentation>
                    Entity type must be unique
                </xs:documentation>
            </xs:annotation>
            <xs:selector xpath="entity" />
            <xs:field xpath="@type" />
        </xs:unique>
    </xs:element>

    <xs:complexType name="entityDeclaration">
        <xs:annotation>
            <xs:documentation>
                Entity declaration
            </xs:documentation>
        </xs:annotation>
        <xs:sequence>
            <xs:element name="attribute" type="attributeDeclaration" minOccurs="1" maxOccurs="unbounded">
                <xs:unique name="uniqueFieldCode">
                    <xs:annotation>
                        <xs:documentation>
                            Field code must be unique
                        </xs:documentation>
                    </xs:annotation>
                    <xs:selector xpath="field" />
                    <xs:field xpath="@code" />
                </xs:unique>
            </xs:element>
        </xs:sequence>
        <xs:attribute name="type" type="identifierType" use="required" />
    </xs:complexType>

    <xs:complexType name="attributeDeclaration">
        <xs:annotation>
            <xs:documentation>
                Attribute declaration
            </xs:documentation>
        </xs:annotation>
        <xs:sequence>
            <xs:element name="field" type="fieldDeclaration" minOccurs="1" maxOccurs="unbounded" />
        </xs:sequence>
        <xs:attribute name="code" type="identifierType" use="required" />
    </xs:complexType>

    <xs:complexType name="fieldDeclaration">
        <xs:annotation>
            <xs:documentation>
                Field declaration
            </xs:documentation>
        </xs:annotation>
        <xs:attribute name="code" type="identifierType" use="required" />
        <xs:attribute name="locked" type="xs:boolean" use="required" />
    </xs:complexType>

    <xs:simpleType name="identifierType">
        <xs:annotation>
            <xs:documentation>
                Identifier can contain only [a-z_].
            </xs:documentation>
        </xs:annotation>
        <xs:restriction base="xs:string">
            <xs:pattern value="[a-z_]+" />
        </xs:restriction>
    </xs:simpleType>
</xs:schema>