在 SQL Server 上读取 XML：选择自定义属性答案

【问题标题】：Read XML on SQL Server : Select custom attribute在 SQL Server 上读取 XML：选择自定义属性
【发布时间】：2021-08-02 14:54:00
【问题描述】：

我正在尝试读取 XML，除了名为 :

的属性外，它总体上运行良好

<custom-attribute attribute-id="loyaltyNumber">1234567890</custom-attribute>

我正在尝试获取值“1234567890”

这里是测试代码：

DECLARE @XML XML = '<customers>
<customer customer-no="00000001">
        <credentials>
            <login>test@email.com</login>
        </credentials>
        <profile>
            <preferred-locale>fr_BE</preferred-locale>
            <custom-attributes>
                <custom-attribute attribute-id="ServiceId">1</custom-attribute>
                <custom-attribute attribute-id="loyaltyNumber">1234567890</custom-attribute>
            </custom-attributes>
        </profile>
        <note/>
    </customer>
    <customer customer-no="00000002">
        <credentials>
            <login>test2@email.com</login>
        </credentials>
        <profile>
            <preferred-locale>fr_FR</preferred-locale>
            <custom-attributes>
                <custom-attribute attribute-id="loyaltyNumber">1234567890</custom-attribute>
            </custom-attributes>
        </profile>
        <note/>
    </customer>
</customers>'
 
SELECT
    CustomerNo = Events.value('@customer-no', 'int'),
    --EventType = Events.value('@Type', 'varchar(20)'),
    CustomerLogin =Events.value('(credentials/login)[1]', 'varchar(60)'),
    CustomerLocal =Events.value('(profile/preferred-locale)[1]', 'varchar(60)'),
    EventKind =Events.value('(profile/custom-attributes/custom-attribute)[2]', 'varchar(60)')
FROM
    @XML.nodes('/customers/customer') AS XTbl(Events)

目前的结果是：

CustomerNo	CustomerLogin	CustomerLocal	EventKind
1	test@email.com	fr_BE	1234567890
2	test2@email.com	fr_FR	NULL

这是合乎逻辑的，因为自定义属性是可选的，因此您无法使用索引访问它们。所以我正在寻找一种按名称访问它们的方法：attribute-id="loyaltyNumber"

谢谢，

【问题讨论】：

你应该在每个 XQuery 之后添加/text() 以获取节点的内部文本，否则会很慢

标签： sql-server sql-server-2019 readxml

【解决方案1】：

..过滤具有attribute-id =“loyaltyNumber”的属性的路径

EventKind =Events.value('(profile/custom-attributes/custom-attribute[@attribute-id="loyaltyNumber"])[1]', 'varchar(60)')

【讨论】：

【解决方案2】：

您可以将自定义属性的属性 ID 添加到您的查询中：

DECLARE @XML XML = '<customers>
<customer customer-no="00000001">
        <credentials>
            <login>test@email.com</login>
        </credentials>
        <profile>
            <preferred-locale>fr_BE</preferred-locale>
            <custom-attributes>
                <custom-attribute attribute-id="ServiceId">1</custom-attribute>
                <custom-attribute attribute-id="loyaltyNumber">1234567890</custom-attribute>
            </custom-attributes>
        </profile>
        <note/>
    </customer>
    <customer customer-no="00000002">
        <credentials>
            <login>test2@email.com</login>
        </credentials>
        <profile>
            <preferred-locale>fr_FR</preferred-locale>
            <custom-attributes>
                <custom-attribute attribute-id="loyaltyNumber">1234567777</custom-attribute>
            </custom-attributes>
        </profile>
        <note/>
    </customer>
</customers>'
 
SELECT
    CustomerNo = Events.value('@customer-no', 'int'),
    --EventType = Events.value('@Type', 'varchar(20)'),
    CustomerLogin =Events.value('(credentials/login)[1]', 'varchar(60)'),
    CustomerLocal =Events.value('(profile/preferred-locale)[1]', 'varchar(60)'),
    EventKind =Events.value('(profile/custom-attributes/custom-attribute[@attribute-id = "loyaltyNumber"])[1]', 'varchar(60)')
FROM
 @XML.nodes('/customers/customer') AS XTbl(Events)

【讨论】：

非常感谢！