mysql如何查询xml

CREATE TABLE books (
    id INT PRIMARY KEY,
    xml_data XML
);

INSERT INTO books (id, xml_data) VALUES
(1, '<book><title>MySQL入门</title><author>张三</author></book>'),
(2, '<book><title>Java编程思想</title><author>李四</author></book>');

SELECT 
    id, 
    EXTRACTVALUE(xml_data, '/book/title') AS title, 
    EXTRACTVALUE(xml_data, '/book/author') AS author 
FROM 
    books;

SELECT 
    id, 
    XMLQUERY('/book/title' PASSING xml_data RETURNING CONTENT) AS title, 
    XMLQUERY('/book/author' PASSING xml_data RETURNING CONTENT) AS author 
FROM 
    books;

SELECT 
    id, 
    EXTRACTVALUE(xml_data, '/book/title') AS title, 
    EXTRACTVALUE(xml_data, '/book/author') AS author 
FROM 
    books 
WHERE 
    id = 1;