SQL Server使用XMLQUERY解析XML Nodes数组。

Question

我正试图解析一个XML Array的节点，这是一个nvarchar(max)列转换为XML，我已经用google搜索了，也搜索了stackoverflow，但我没有找到任何可能帮助我解决这个问题的例子。

我有一个存储为nvarchar(max)的XML值，格式如下。

<?xml version="1.0" encoding="utf-16"?>
<ArrayOfCmnStatusRuleOverride xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    <cmnStatusRuleOverride xsi:type="cmnCoveredByOverride">
        <Start>2020-05-28T17:00:00</Start>
        <End>2020-05-29T07:00:00</End>
        <SuspendExpiration>0001-01-01T00:00:00</SuspendExpiration>
        <subID>103</subID>
        <listID>4016</listID>
        <Description>Jane Doe</Description>
    </cmnStatusRuleOverride>
    <cmnStatusRuleOverride xsi:type="cmnCoveredByOverride">
        <Start>2020-05-26T17:00:00</Start>
        <End>2020-05-28T07:00:00</End>
        <SuspendExpiration>0001-01-01T00:00:00</SuspendExpiration>
        <subID>103</subID>
        <listID>4014</listID>
        <Description>Joe Blow</Description>
    </cmnStatusRuleOverride>
    <cmnStatusRuleOverride xsi:type="cmnCoveredByOverride">
        <Start>2020-05-25T17:00:00</Start>
        <End>2020-05-26T07:00:00</End>
        <SuspendExpiration>0001-01-01T00:00:00</SuspendExpiration>
        <subID>103</subID>
        <listID>4016</listID>
        <Description>Jane Doe</Description>
    </cmnStatusRuleOverride>
</ArrayOfCmnStatusRuleOverride>

我使用下面的SQL来解析内容，这和我的需求很接近，但是交叉应用却给我带来了问题。

declare @Status xml, @Override nvarchar(100),@ORStart nvarchar(50), @OREnd nvarchar(50)
set @Status = 
(select b.Overrides from Database.dbo.Descriptions as a
inner join Database.dbo.Listings as b on a.listID = b.listId
inner join Database.dbo.Clients as c on b.subId = c.subId and cast(c.ClientNumber as nvarchar) = '2195956693'
--cross apply @Status.nodes('/ArrayOfCmnStatusRuleOverride/cmnStatusRuleOverride/Description') as T(Loc)
where a.Description = 'Jack Sprat')

select T.OVR.query('.') 'Override'--, T1.STT.query('.') 'Start'--, T2.ENND.query('.') 'End'
from Database.dbo.Descriptions as a
inner join Database.dbo.Listings as b on a.listID = b.listId
inner join Database.dbo.Clients as c on b.subId = c.subId and cast(c.ClientNumber as nvarchar) = '9876543210'
cross apply @Status.nodes('/ArrayOfCmnStatusRuleOverride/cmnStatusRuleOverride/Description') as T(OVR)
--cross apply T.OVR.nodes('/ArrayOfCmnStatusRuleOverride/cmnStatusRuleOverride/Start') as T1(STT)
--cross apply T.OVR.nodes('/ArrayOfCmnStatusRuleOverride/cmnStatusRuleOverride/End') as T2(ENND)
where a.Description = 'Jack Sprat'

将第二个和第三个xml查询注释掉，我得到3个结果，正如我所期望的那样。

1. 无名氏
2. Joe Blow
3. 无名氏

如果我取消第二个查询，那么我得到9个结果，如下图所示

    Override        Start

1. 无名氏 2020-05-28T17:00:00
2. 无名氏 2020-05-26T17:00:00
3. 无名氏 2020-05-25T17:00:00
4. 乔布洛 2020-05-28T17:00:00
5. 乔吹 2020-05-26T17:00:00
6. 乔吹 2020-05-25T17:00:00
7. 无名氏 2020-05-28T17:00:00
8. 无名氏 2020-05-26T17:00:00
9. 无名氏 2020-05-25T17:00:00

当然，如果我取消第三个查询，我得到的是27行。 有什么提示，我做错了什么？ 我从昨天早上开始就一直在用这个方法想弄明白这个问题，就差那么一点，却又那么远。

Answer 1

想出了它。

select T.OVR.query('./Description') 'Override', 
T.OVR.query('./Start') 'Start', 
T.OVR.query('./End') 'End'
from Database.dbo.Descriptions as a
inner join Database.dbo.Listings as b on a.listID = b.listId
inner join Database.dbo.Clients as c on b.subId = c.subId and cast(c.ClientNumber as nvarchar) = '9876543210'
cross apply @Status.nodes('/ArrayOfCmnStatusRuleOverride/cmnStatusRuleOverride') as T(OVR)
where a.Description = 'Jack Sprat'