使用 oracle sql 对 XML 中的子节点求和

Question

我有以下格式的 XML

<Receive
    xmlns:xsd="http://www.w3.org/2001/XMLSchema"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    <Date>20171106</Date>
    <ReceiptDetails>
        <ReceiptDetail>
            <Quantity>3</Quantity>
        </ReceiptDetail>
        <ReceiptDetail>
            <Quantity>2</Quantity>
        </ReceiptDetail>
        <ReceiptDetail>
            <Quantity>1</Quantity>
        </ReceiptDetail>
        <ReceiptDetail>
            <Quantity>4</Quantity>
        </ReceiptDetail>
    </ReceiptDetails>
</Receive>

现在我想要一个查询 Oracle SQL 查询，它返回数量节点的总和。

我编写了一个连接值的查询。

SELECT 
 XMLTYPE(t.REQ_MSG).EXTRACT('//Receive/ReceiptDetails/ReceiptDetail/Quantity/text()').getStringVal()
FROM 
   TABLE_NAME t;

这给了我 3214，这是连接的值，但我想要 10，这是总和。

Answer 1

考虑使用 XMLTABLE 将 XML 节点解析为列，然后在外部查询中聚合。

SELECT  SUM(e.Quantity) AS SumQuantity

FROM  XMLTABLE('/Receive/ReceiptDetails/ReceiptDetail' 
      PASSING XMLTYPE('<Receive xmlns:xsd="http://www.w3.org/2001/XMLSchema"
                                xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
                            <Date>20171106</Date>
                            <ReceiptDetails>
                                <ReceiptDetail>
                                    <Quantity>3</Quantity>
                                </ReceiptDetail>
                                <ReceiptDetail>
                                    <Quantity>2</Quantity>
                                </ReceiptDetail>
                                <ReceiptDetail>
                                    <Quantity>1</Quantity>
                                </ReceiptDetail>
                                <ReceiptDetail>
                                    <Quantity>4</Quantity>
                                </ReceiptDetail>
                            </ReceiptDetails>
                        </Receive>')
       COLUMNS
        Quantity NUMBER PATH 'Quantity') as e

对于表中的 XML 列

SELECT  SUM(e.Quantity) AS SumQuantity

FROM  MY_TABLE,
      XMLTABLE('/Receive/ReceiptDetails/ReceiptDetail' 
      PASSING XMLTYPE(MY_TABLE.MY_XML_COLUMN)

      COLUMNS
        Quantity NUMBER PATH 'Quantity') as e

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