SQL 如何在sql中的单个视图中加入两个视图？
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how to join two views in single View in sql?
提问by Sarfaraz Ali
I have two Views I want to merge into single view for example
例如，我有两个视图要合并为单个视图
View 1 is defined as:
视图 1 定义为：
CREATE VIEW view1 AS
select DV.demValueId,DV.value,DE.demElementId,DE.name,
DES.demElementSetGroupId,DR.demRecordId,DR.name as Role,
DR.demClusterSetGroupRef,L.EmailId
from DemographicsDataValue DV
inner join DemographicsElement DE
on DV.demValueId=DE.demValueRef
inner join DemographicsElementSet DES
on DE.demElementId=DES.demElementRef
inner join DemographicsRecord DR
on DR.demElementSetGroupRef=DES.demElementSetGroupId
inner join LoginDetail L
on DR.demRecordId=L.demRecordIdRef
View 2 is defined as:
视图 2 定义为：
CREATE VIEW view2
AS
select DV.valueId, DV.value,E.ElementId,E.name,
ES.ElementSetGroupId,ET.entryId,ET.name as E_Name,
ET.SystemDateTime,C.compositionId,C.linkSetRef
from DataValue DV
inner join Element E
on DV.valueId=E.valueRef
inner join ElementSet ES
on E.ElementId=ES.ElementRef
inner join Entry ET
on ES.elementSetGroupId=ET.elementSetGroupRef
inner join EntrySet ESG
on ESG.entryRef=ET.entryId
inner Join Section S
on s.entrySetGroupRef=ESG.entrySetGroupId
inner join SectionSet SS
on SS.sectionRef=S.sectionId
where S.name='Appointment'
How do I combine them into a single view select * from View1 Select * from View2
如何将它们组合成一个视图 select * from View1 Select * from View2
output into single query
输出到单个查询
please help
请帮忙
回答by CM2K
if you want the common fields you can do:
如果你想要常见的字段，你可以这样做：
select * FROM View1
inner join View2 -- or you can do a left join here
on View1.Column = View2.Column -- and ... add more if needed
If the table structure is the same for both and you don't care about duplicates you can do an union allif you care about the duplicates then union
如果两者的表结构相同并且您不关心重复项，则可以执行union allif 您关心重复项union
select * from View1
union all
select * from View2
回答by Alex Gidan
Use unionif you have homogeneous columns. Otherwise use Joinon a suitable field
union如果您有同质列，请使用。否则Join在合适的领域使用
SELECT *
FROM view1
INNER JOIN view2 ON view1.id = view2.ref;
More details are needed to know which join to use and on which fields.
需要更多详细信息才能知道要使用哪个联接以及在哪些字段上使用。
