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SQL 联合查询与XML解析实例

这里举例说明如何实现该功能：

(select a.EBILLNO,
a.EMPNAME,
a.APPLYDATE,
b.HS_NAME,
replace(replace(a.SUMMARY,char(10), ''),char(13),'') as SUMMARY,
cast(c.XmlData as XML).value('(/List/item/No/text())[1]','NVARCHAR(300)') as No,
cast(c.XmlData as XML).value('(/List/item/zje/text())[1]','NVARCHAR(300)') as zje,
cast(c.XmlData as XML).value('(/List/item/yfje/text())[1]','NVARCHAR(300)') as yfje,
cast(c.XMLData as XML).value('(/List/item/bcje/text())[1]','NVARCHAR(300)') as bcje,
cast(c.XMLData as XML).value('(/List/item/URL/text())[1]','NVARCHAR(300)') as URL,
cast(c.XMLData as XML).value('(/List/item/Remark/text())[1]','NVARCHAR(300)') as BZ,
cast(p.XMLData as XML).value('(/NewDataSet/Table1/UserName/text())[1]','NVARCHAR(500)') as SKRXM,
('http://……?sid=3&mid=7281&PID='+a.PID) as bxdljdz
from Ex_Bill as a 
left join Ex_System_Cfg as b on(a.BILLSYSTEMID=b.HS_ID and a.DATASYSTEMID=b.SYSTEM_NAME)
left join (select * from [10.2.3.39].AspireworkFlow.dbo.RepeaingTable) as c on (c.Keyword='URL' and c.ProcessID=a.PID)
left join (select * from [10.2.3.39].AspireworkFlow.dbo.RepeaingTable) as d on (d.Keyword='FKXX_New' and d.ProcessID=a.PID or d.Keyword='FKXX' and d.ProcessID=a.PID)
left join (select * from EX_BillExtension) as p on a.BILLNO=p.BILL_NO

where applyempid='zhongxun' and a.EBILLNO is not null
and status>5 and status not in(200,100,7000)
and a.APPLYDATE>'2011-01-01'
and a.HT='是'
and cast(d.XMLData as XML).value('(/List/item/SKRXM/text())[1]','NVARCHAR(300)') is null) 
union
(select e.EBILLNO,
e.EMPNAME,
e.APPLYDATE,
f.HS_NAME,
replace(replace(e.SUMMARY,char(10), ''),char(13),'') as SUMMARY,
cast(g.XmlData as XML).value('(/List/item/No/text())[1]','NVARCHAR(300)') as No,
cast(g.XmlData as XML).value('(/List/item/zje/text())[1]','NVARCHAR(300)') as zje,
cast(g.XmlData as XML).value('(/List/item/yfje/text())[1]','NVARCHAR(300)') as yfje,
cast(g.XMLData as XML).value('(/List/item/bcje/text())[1]','NVARCHAR(300)') as bcje,
cast(g.XMLData as XML).value('(/List/item/URL/text())[1]','NVARCHAR(300)') as URL,
cast(g.XMLData as XML).value('(/List/item/Remark/text())[1]','NVARCHAR(300)') as BZ,
cast(h.XMLData as XML).value('(/List/item/SKRXM/text())[1]','NVARCHAR(300)') as SKRXM,
('http://……?sid=3&mid=7281&PID='+e.PID) as bxdljdz
from Ex_Bill as e 
left join Ex_System_Cfg as f on(e.BILLSYSTEMID=f.HS_ID and e.DATASYSTEMID=f.SYSTEM_NAME)
left join (select * from [10.2.3.39].AspireworkFlow.dbo.RepeaingTable) as g on (g.Keyword='URL' and g.ProcessID=e.PID)
left join (select * from [10.2.3.39].AspireworkFlow.dbo.RepeaingTable) as h on (h.Keyword='FKXX_New' and h.ProcessID=e.PID or h.Keyword='FKXX' and h.ProcessID=e.PID)

where applyempid='zhongxun' and e.EBILLNO is not null
and status>5 and status not in(200,100,7000)
and e.APPLYDATE>'2011-01-01'
and e.HT='是'
and cast(h.XMLData as XML).value('(/List/item/SKRXM/text())[1]','NVARCHAR(300)') is not null)

在写SQL的时候，难点不在于SQL本身，而在于逻辑上，当写出这个SQL以后，发现逻辑也没有那么难了。

就是采用Union把两组都查询出来的表放到一个里面

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