从另一个表中将标识列值插入表中？

Question

create table #test (a int identity(1,1), b varchar(20), c varchar(20))

insert into #test (b,c) values ('bvju','hjab')
insert into #test (b,c) values ('bst','sdfkg')
......
insert into #test (b,c) values ('hdsj','kfsd')

如何将从上面的插入语句填充的标识值（ #test.a ）插入#sample表（另一个表）

create table #sample (d int identity(1,1), e int, f varchar(20))

insert into #sample(e,f) values (identity value from #test table, 'jkhjk')
insert into #sample(e,f) values (identity value from #test table, 'hfhfd')
......
insert into #sample(e,f) values (identity value from #test table, 'khyy')

任何人都可以解释一下如何为更大的记录集（数千条记录）实现这一点吗？

我们可以使用while循环和scope_identity吗？ 如果是这样，请说明我们该怎么办？

如果我从选择查询中插入#test会是什么情况？

插入#test（b，c）select ... from ...（数千条记录）

我如何捕获身份值并将该值用于另一个（#sample）插入#sample（e，f）select（来自#test的身份值），......来自......（千条记录） -

Answer 1

您可以使用output子句。 从文档（强调我的）：

OUTPUT子句从INSERT，UPDATE，DELETE或MERGE语句影响的每一行返回信息或基于表达式的表达式。 这些结果可以返回到处理应用程序，以用于确认消息，存档和其他此类应用程序要求。 结果也可以插入表或表变量中。 此外，您可以在嵌套的INSERT，UPDATE，DELETE或MERGE语句中捕获OUTPUT子句的结果，并将这些结果插入目标表或视图中。

像这样：

create table #tempids (a int) -- a temp table for holding our identity values

insert into #test 
(b,c) 
output inserted.a into #tempids -- put the inserted identity value into #tempids
values 
('bvju','hjab')

然后你问......

如果插入来自选择，该怎么办？

它的工作方式相同......

insert into #test 
(b,c) 
output inserted.a into #tempids -- put the inserted identity value into #tempids
select -- except you use a select here
 Column1 ,Column2 from SomeSource

无论是从值，派生表，执行语句，dml表源还是默认值插入，它的工作方式都相同。 如果您插入1000条记录，您将在#tempids获得1000个ID。

Answer 2

我刚刚用输出子句写了一个“基于集合”的样本。

这里是。

IF OBJECT_ID('tempdb..#DestinationPersonParentTable') IS NOT NULL
begin
        drop table #DestinationPersonParentTable
end



IF OBJECT_ID('tempdb..#DestinationEmailAddressPersonChildTable') IS NOT NULL
begin
        drop table #DestinationEmailAddressPersonChildTable
end



CREATE TABLE #DestinationPersonParentTable
(
PersonParentSurrogateIdentityKey int not null identity (1001, 1), 
SSNNaturalKey int, 
HireDate datetime
)



declare @PersonOutputResultsAuditTable table
(
SSNNaturalKey int, 
PersonParentSurrogateIdentityKeyAudit int
)





CREATE TABLE #DestinationEmailAddressPersonChildTable
(
DestinationChildSurrogateIdentityKey int not null identity (3001, 1), 
PersonParentSurrogateIdentityKeyFK int, 
EmailAddressValueNaturalKey varchar(64),
EmailAddressType int
)





-- Declare XML variable

DECLARE @data XML;

-- Element-centered XML

SET @data = N'
<root xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    <Person>
        <SSN>222222222</SSN>
        <HireDate>2002-02-02</HireDate>
    </Person>

    <Person>
        <SSN>333333333</SSN>
        <HireDate>2003-03-03</HireDate>
    </Person>

    <EmailAddress>
        <SSNLink>222222222</SSNLink>
        <EmailAddressValue>g@g.com</EmailAddressValue>
        <EmailAddressType>1</EmailAddressType>
    </EmailAddress>

    <EmailAddress>
        <SSNLink>222222222</SSNLink>
        <EmailAddressValue>h@h.com</EmailAddressValue>
        <EmailAddressType>2</EmailAddressType>
    </EmailAddress>

    <EmailAddress>
        <SSNLink>333333333</SSNLink>
        <EmailAddressValue>a@a.com</EmailAddressValue>
        <EmailAddressType>1</EmailAddressType>
    </EmailAddress>

    <EmailAddress>
        <SSNLink>333333333</SSNLink>
        <EmailAddressValue>b@b.com</EmailAddressValue>
        <EmailAddressType>2</EmailAddressType>
    </EmailAddress>

</root>

';




INSERT INTO #DestinationPersonParentTable ( SSNNaturalKey ,  HireDate )

output inserted.SSNNaturalKey , inserted.PersonParentSurrogateIdentityKey  into @PersonOutputResultsAuditTable ( SSNNaturalKey , PersonParentSurrogateIdentityKeyAudit)

SELECT T.parentEntity.value('(SSN)[1]', 'INT') AS SSN,
       T.parentEntity.value('(HireDate)[1]', 'datetime') AS HireDate
FROM @data.nodes('root/Person') AS T(parentEntity)
/* add a where not exists check on the natural key */
where not exists (
    select null from #DestinationPersonParentTable innerRealTable where innerRealTable.SSNNaturalKey = T.parentEntity.value('(SSN)[1]', 'INT') )
;

/* Optional.  You could do a UPDATE here based on matching the #DestinationPersonParentTableSSNNaturalKey = T.parentEntity.value('(SSN)[1]', 'INT')
You could Combine INSERT and UPDATE using the MERGE function on 2008 or later.
 */


select 'PersonOutputResultsAuditTable_Results' as Label, * from @PersonOutputResultsAuditTable


INSERT INTO #DestinationEmailAddressPersonChildTable (  PersonParentSurrogateIdentityKeyFK ,  EmailAddressValueNaturalKey , EmailAddressType )
SELECT  par.PersonParentSurrogateIdentityKeyAudit , 
        T.childEntity.value('(EmailAddressValue)[1]', 'varchar(64)') AS EmailAddressValue,
        T.childEntity.value('(EmailAddressType)[1]', 'INT') AS EmailAddressType
FROM @data.nodes('root/EmailAddress') AS T(childEntity)
/* The next join is the "trick".  Join on the natural key (SSN)....**BUT** insert the PersonParentSurrogateIdentityKey into the table */
join @PersonOutputResultsAuditTable par on par.SSNNaturalKey = T.childEntity.value('(SSNLink)[1]', 'INT')
where not exists (
    select null from #DestinationEmailAddressPersonChildTable innerRealTable where innerRealTable.PersonParentSurrogateIdentityKeyFK = par.PersonParentSurrogateIdentityKeyAudit AND  innerRealTable.EmailAddressValueNaturalKey = T.childEntity.value('(EmailAddressValue)[1]', 'varchar(64)'))
;



print '/#DestinationPersonParentTable/'
select * from #DestinationPersonParentTable


print '/#DestinationEmailAddressPersonChildTable/'
select * from #DestinationEmailAddressPersonChildTable


select SSNNaturalKey , HireDate , '---' as Sep1 , EmailAddressValueNaturalKey , EmailAddressType , '---' as Sep2, par.PersonParentSurrogateIdentityKey as ParentPK , child.PersonParentSurrogateIdentityKeyFK as childFK from #DestinationPersonParentTable par join #DestinationEmailAddressPersonChildTable child
on par.PersonParentSurrogateIdentityKey = child.PersonParentSurrogateIdentityKeyFK



IF OBJECT_ID('tempdb..#DestinationPersonParentTable') IS NOT NULL
begin
        drop table #DestinationPersonParentTable
end


IF OBJECT_ID('tempdb..#DestinationEmailAddressPersonChildTable') IS NOT NULL
begin
        drop table #DestinationEmailAddressPersonChildTable
end

Answer 3

insert into #test (b,c) values ('bvju','hjab')
insert into #sample(e,f) values (@SCOPE_IDENTITY(), 'jkhjk')

@SCOPE_IDENTITY（）返回使用的最后一个标识值