使用 SQL 从 XML 中获取值答案

【问题标题】：Get values from XML using SQL使用 SQL 从 XML 中获取值
【发布时间】：2021-07-09 08:42:44
【问题描述】：

我是 SQL 新手，我想知道如何从下面的 XML 中获取值“123189”、“OK”和“OK”？我使用的是下面的 SELECT，但是当我调用此过程时，参数（nMaxRate、vMaxRateValid 和 vMaxRateVariation）保持为空。

选择：

select extractvalue(Value(t), '/soap:max_rate', ''),
                   extractvalue(Value(t), '/soap:max_rate_valid', ''),
                   extractvalue(Value(t), '/soap:max_rate_variation', '') 
                   into nMaxRate , vMaxRateValid, vMaxRateVariation
                   from TABLE(xmlSequence(extract(response_xml,  '/soap:check_avg_rateResponse/soap:check_avg_rateResult', 
                    ''))) t;

response_xml：

<senv:Envelope xmlns:senv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:soap="http://schemas.xmlsoap.org/wsdl/soap/">
   <senv:Body>
      <soap:check_avg_rateResponse>
         <soap:check_avg_rateResult>
            <soap:max_rate>123189</soap:max_rate>
            <soap:max_rate_valid>OK</soap:max_rate_valid>
            <soap:max_rate_variation>OK</soap:max_rate_variation>
         </soap:check_avg_rateResult>
      </soap:check_avg_rateResponse>
   </senv:Body>
</senv:Envelope>

【问题讨论】：

标签： sql oracle stored-procedures plsql plsql-package

【解决方案1】：

使用xmltable 和xmlnamespaces 子句来指定您的命名空间：

with rws as ( select xmltype ('
<senv:Envelope xmlns:senv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:soap="http://schemas.xmlsoap.org/wsdl/soap/">
   <senv:Body>
      <soap:check_avg_rateResponse>
         <soap:check_avg_rateResult>
            <soap:max_rate>123189</soap:max_rate>
            <soap:max_rate_valid>OK</soap:max_rate_valid>
            <soap:max_rate_variation>OK</soap:max_rate_variation>
         </soap:check_avg_rateResult>
      </soap:check_avg_rateResponse>
   </senv:Body>
</senv:Envelope>' ) x from dual
) 
  select s.* from rws, xmltable (
    xmlnamespaces ( 
      'http://schemas.xmlsoap.org/soap/envelope/' as "senv",  
      'http://schemas.xmlsoap.org/wsdl/soap/' as "soap" 
    ), 
    '/senv:Envelope/senv:Body/soap:check_avg_rateResponse/soap:check_avg_rateResult'
    passing rws.x
    columns 
      max_rate int path 'soap:max_rate',
      max_rate_valid varchar2(10) path 'soap:max_rate_valid',
      max_rate_variation varchar2(10) path 'soap:max_rate_variation'
  ) s;
  
MAX_RATE MAX_RATE_VALID   MAX_RATE_VARIATION   
  123189 OK               OK

【讨论】：

【解决方案2】：

你想使用XMLNAMESPACES和XMLTABLE：

DECLARE
  response_xml CLOB := '<senv:Envelope xmlns:senv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:soap="http://schemas.xmlsoap.org/wsdl/soap/">
   <senv:Body>
      <soap:check_avg_rateResponse>
         <soap:check_avg_rateResult>
            <soap:max_rate>123189</soap:max_rate>
            <soap:max_rate_valid>OK</soap:max_rate_valid>
            <soap:max_rate_variation>OK</soap:max_rate_variation>
         </soap:check_avg_rateResult>
      </soap:check_avg_rateResponse>
   </senv:Body>
</senv:Envelope>';
  nMaxRate          NUMBER;
  vMaxRateValid     VARCHAR2(10);
  vMaxRateVariation VARCHAR2(10);
BEGIN
  SELECT max_rate,
         max_rate_valid,
         max_rate_variation
  INTO   nMaxRate,
         vMaxRateValid,
         vMaxRateVariation
  FROM   XMLTABLE(
           XMLNAMESPACES(
             'http://schemas.xmlsoap.org/soap/envelope/' AS "senv",
             'http://schemas.xmlsoap.org/wsdl/soap/' AS "soap"
           ),
           '/senv:Envelope/senv:Body/soap:check_avg_rateResponse/soap:check_avg_rateResult'
           PASSING XMLTYPE(response_xml)
           COLUMNS
             max_rate           NUMBER       PATH './soap:max_rate',
             max_rate_valid     VARCHAR2(10) PATH './soap:max_rate_valid',
             max_rate_variation VARCHAR2(10) PATH './soap:max_rate_variation'
         );
  DBMS_OUTPUT.PUT_LINE( nMaxRate );
  DBMS_OUTPUT.PUT_LINE( vMaxRateValid );
  DBMS_OUTPUT.PUT_LINE( vMaxRateVariation );
END;
/

哪些输出：

123189
OK
OK

db小提琴here

【讨论】：