我正在尝试在 PL/SQL 中解析 XML。我无法从标签中检索属性值，我做错了啥？

Posted 2023-03-27

【中文标题】我正在尝试在 PL/SQL 中解析 XML。我无法从标签中检索属性值，我做错了啥？

【英文标题】：I'm trying to parse an XML in PL/SQL. I am unable to retrieve the attribute values from a tag, what am i doing wrong?我正在尝试在 PL/SQL 中解析 XML。我无法从标签中检索属性值，我做错了什么？

【发布时间】：2019-10-15 06:53:44

【问题描述】：

以下 XML 将无法解析。请找到我正在使用的确切代码 -

DECLARE
  x XMLType := XMLType(
    '<ns0:CreateSODSOrder xmlns:ns0="http://schemas.dell.com/services/isp/OrderHistory/3.5" xmlns:soap-env="http://schemas.xmlsoap.org/soap/envelope/" MessageType="CREATE">
  <ns0:CreateOrder>
    <ns0:SalesOrder ORDER_NUM="302199286" DPID="GB2003-2120-85049" PO_NUM="test" ORDER_BUID="202" DPS_NUM="" CHANNEL="ENTP" SUB_CHANNEL="GB_IC1A" ORDER_TYPE="GB ENT Order" REBOOKED_ORDER_NUM="" SALES_REP_NAME="SANJANA_D_C" ORIGINAL_ORDER_REF_NUM="" AMF_ORDER_NUM="" IR_NUM="GB2003-2120-85049" CCN="GB_IC1A" CUSTOMER_NUM="GB90117414" CUSTOMER_BUID="202" ORDER_DATE="2019-09-30T07:59:32" COUNTRY_NUM="GB" CCN_DESC="GB Indirect Certified  Tier 1A"/>
  </ns0:CreateOrder>
</ns0:CreateSODSOrder>');
BEGIN
  FOR r IN (
    SELECT ExtractValue(column_value,'Sales/@ORDER_NAME') as name
         -- ,ExtractValue(Value(p),'/row/Address/State/text()') as state
          --,ExtractValue(Value(p),'/row/Address/City/text()') as city
    FROM   TABLE(XMLSequence(Extract(x,'/CreateSODSOrder/CreateOrder/SalesOrder')))
    ) LOOP
          dbms_output.put_line(r.name);
  END LOOP;
    dbms_output.put_line('out');
END;

当我将 ns0: 与 CreateSODSOrder/CreateOrder/SalesOrder 一起使用时，它会引发 XML 解析错误。

【参考方案1】：

您收到 XML 解析错误，因为缺少命名空间定义。 以下代码将解决命名空间问题，但在不知道您的意图的情况下很难获取值

DECLARE
  x XMLType := XMLType(
    '<ns0:CreateSODSOrder xmlns:ns0="http://schemas.dell.com/services/isp/OrderHistory/3.5" xmlns:soap-env="http://schemas.xmlsoap.org/soap/envelope/" MessageType="CREATE">
  <ns0:CreateOrder>
    <ns0:SalesOrder ORDER_NUM="302199286" DPID="GB2003-2120-85049" PO_NUM="test" ORDER_BUID="202" DPS_NUM="" CHANNEL="ENTP" SUB_CHANNEL="GB_IC1A" ORDER_TYPE="GB ENT Order" REBOOKED_ORDER_NUM="" SALES_REP_NAME="SANJANA_D_C" ORIGINAL_ORDER_REF_NUM="" AMF_ORDER_NUM="" IR_NUM="GB2003-2120-85049" CCN="GB_IC1A" CUSTOMER_NUM="GB90117414" CUSTOMER_BUID="202" ORDER_DATE="2019-09-30T07:59:32" COUNTRY_NUM="GB" CCN_DESC="GB Indirect Certified  Tier 1A"/>
  </ns0:CreateOrder>
</ns0:CreateSODSOrder>');
BEGIN
  FOR r IN (
    SELECT ExtractValue(column_value,'Sales/@ORDER_NAME') as name
         -- ,ExtractValue(Value(p),'/row/Address/State/text()') as state
          --,ExtractValue(Value(p),'/row/Address/City/text()') as city
    FROM   TABLE(XMLSequence(Extract(x,'/ns0:CreateSODSOrder/ns0:CreateOrder/ns0:SalesOrder', 'xmlns:ns0="http://schemas.dell.com/services/isp/OrderHistory/3.5"' )))
    ) LOOP
          dbms_output.put_line(r.name);
  END LOOP;
    dbms_output.put_line('out');
END;

使用XMLTABLE 是个好主意，因为ExtractValue 有点过时且不推荐使用。

下面添加了获取XMLTABLE属性的示例代码。

DECLARE
CURSOR get_data IS
SELECT * 
FROM XMLTABLE(xmlnamespaces('http://schemas.dell.com/services/isp/OrderHistory/3.5' as "ns0", 'http://schemas.xmlsoap.org/soap/envelope/' as "soap-env" ),'ns0:CreateSODSOrder/ns0:CreateOrder/ns0:SalesOrder'
   passing xmltype('<ns0:CreateSODSOrder xmlns:ns0="http://schemas.dell.com/services/isp/OrderHistory/3.5" xmlns:soap-env="http://schemas.xmlsoap.org/soap/envelope/" MessageType="CREATE">
  <ns0:CreateOrder>
    <ns0:SalesOrder ORDER_NUM="302199286" DPID="GB2003-2120-85049" PO_NUM="test" ORDER_BUID="202" DPS_NUM="" CHANNEL="ENTP" SUB_CHANNEL="GB_IC1A" ORDER_TYPE="GB ENT Order" REBOOKED_ORDER_NUM="" SALES_REP_NAME="SANJANA_D_C" ORIGINAL_ORDER_REF_NUM="" AMF_ORDER_NUM="" IR_NUM="GB2003-2120-85049" CCN="GB_IC1A" CUSTOMER_NUM="GB90117414" CUSTOMER_BUID="202" ORDER_DATE="2019-09-30T07:59:32" COUNTRY_NUM="GB" CCN_DESC="GB Indirect Certified  Tier 1A"/>
  </ns0:CreateOrder>
</ns0:CreateSODSOrder>')
           COLUMNS 
           ORDER_NUM      VARCHAR2(30)    PATH '@ORDER_NUM',
           DPID           VARCHAR2(30)    PATH '@DPID');
BEGIN  
FOR rec_ IN get_data LOOP
  dbms_output.put_line(rec_.ORDER_NUM);
  dbms_output.put_line(rec_.DPID);
  END LOOP;
END;