MSSQL查询Xml差异顺序

时间:2017-06-23 00:50:53

标签: sql-server xml tsql xpath xquery

我的数据库需要在用户发送时存储xml请求,而xml有2个Communications元素, WP SA ,但它们不是固定的(我的意思是位置) ):

    <bms:OrgInfo>
      <bms:Communications>
        <bms:CommQualifier>WP</bms:CommQualifier>
        <bms:CommPhone>5555551212</bms:CommPhone>
      </bms:Communications>
      <bms:Communications>
        <bms:CommQualifier>SA</bms:CommQualifier>
        <bms:Address>
          <bms:Address1>1234 Test Avenue</bms:Address1>
          <bms:Address2>1234 Test Avenue</bms:Address2>
          <bms:City>Alamogordo</bms:City>
          <bms:StateProvince>NM</bms:StateProvince>
          <bms:PostalCode>88310</bms:PostalCode>
          <bms:CountryCode>US</bms:CountryCode>
        </bms:Address>
      </bms:Communications>
    </bms:OrgInfo>

有时 SA 元素将是第一个。

如何查询它而不用担心poistion

这是我当前的查询,我用index来查询它:

IF  EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[XmlStore]') AND type in (N'U'))
DROP TABLE [dbo].[XmlStore]
GO

CREATE TABLE [dbo].[XmlStore](
    [XmlRequest] [xml] NULL
) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY]

INSERT INTO [XmlStore]([XmlRequest]) VALUES('<?xml version="1.0" encoding="UTF-8"?>
    <bms:OrgInfo xmlns:bms="http://example.org">
      <bms:Communications>
        <bms:CommQualifier>WP</bms:CommQualifier>
      </bms:Communications>
      <bms:Communications>
        <bms:CommQualifier>SA</bms:CommQualifier>
      </bms:Communications>
      <bms:Communications>
        <bms:CommQualifier>EM</bms:CommQualifier>
      </bms:Communications>
    </bms:OrgInfo>')


;WITH xmlnamespaces ( 'http://example.org' AS bms )
Select
    t.XmlRequest.value('(/bms:OrgInfo/bms:Communications/bms:CommQualifier)[1]', 'nvarchar(100)') as WP_Value,
    t.XmlRequest.value('(/bms:OrgInfo/bms:Communications/bms:CommQualifier)[2]', 'nvarchar(100)') as SA_Value,
    t.XmlRequest.value('(/bms:OrgInfo/bms:Communications/bms:CommQualifier)[3]', 'nvarchar(100)') as EM_Value
FROM [XmlStore] AS t    

DROP TABLE [dbo].[XmlStore]

如果用户重新订购通讯元素,那将是一场灾难!

1 个答案:

答案 0 :(得分:4)

您可以像这里一样添加XQuery predicate

IF  EXISTS (SELECT * FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[XmlStore]') AND type in (N'U'))
DROP TABLE [dbo].[XmlStore]
GO

CREATE TABLE [dbo].[XmlStore](
    [XmlRequest] [xml] NULL
) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY]

INSERT INTO [XmlStore]([XmlRequest]) VALUES('<?xml version="1.0" encoding="UTF-8"?>
    <bms:OrgInfo xmlns:bms="http://example.org">
      <bms:Communications>
        <bms:CommQualifier>WP</bms:CommQualifier>
      </bms:Communications>
      <bms:Communications>
        <bms:CommQualifier>SA</bms:CommQualifier>
      </bms:Communications>
      <bms:Communications>
        <bms:CommQualifier>EM</bms:CommQualifier>
      </bms:Communications>
    </bms:OrgInfo>')

- 再次使用XML,但顺序不同

INSERT INTO [XmlStore]([XmlRequest]) VALUES('<?xml version="1.0" encoding="UTF-8"?>
    <bms:OrgInfo xmlns:bms="http://example.org">
      <bms:Communications>
        <bms:CommQualifier>SA</bms:CommQualifier>
      </bms:Communications>
      <bms:Communications>
        <bms:CommQualifier>EM</bms:CommQualifier>
      </bms:Communications>
      <bms:Communications>
        <bms:CommQualifier>WP</bms:CommQualifier>
      </bms:Communications>
    </bms:OrgInfo>')

- 查询(所有索引均为[1]

;WITH xmlnamespaces ( 'http://example.org' AS bms )
Select
    t.XmlRequest.value('(/bms:OrgInfo/bms:Communications[bms:CommQualifier="WP"]/bms:CommQualifier)[1]', 'nvarchar(100)') as WP_Value,
    t.XmlRequest.value('(/bms:OrgInfo/bms:Communications[bms:CommQualifier="SA"]/bms:CommQualifier)[1]', 'nvarchar(100)') as SA_Value,
    t.XmlRequest.value('(/bms:OrgInfo/bms:Communications[bms:CommQualifier="EM"]/bms:CommQualifier)[1]', 'nvarchar(100)') as EM_Value
FROM [XmlStore] AS t    

DROP TABLE [dbo].[XmlStore]