newsupernova/vendor/magento/framework/Setup/Declaration/Schema/etc/name.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" elementFormDefault="qualified">
    <xs:simpleType name="nameType">
        <xs:annotation>
            <xs:documentation>
                We can`t create column index or constraint with name length more than 64 char
            </xs:documentation>
        </xs:annotation>
        <xs:restriction base="xs:string">
            <xs:maxLength value="64" />
        </xs:restriction>
    </xs:simpleType>
    <xs:simpleType name="referenceIdType">
        <xs:union memberTypes="nameType">
            <xs:simpleType>
                <xs:annotation>
                    <xs:documentation>
                        The attribute can contain only [A-Z0-9_].
                    </xs:documentation>
                </xs:annotation>
                <xs:restriction base="xs:string">
                    <xs:pattern value="[A-Z0-9_]+" />
                </xs:restriction>
            </xs:simpleType>
        </xs:union>
    </xs:simpleType>
</xs:schema>