Loopback linked servers

I want to set a server up to be able to reference itself
via an alias in a 4-part name. Let us call the server
SQLSERVER and its alias BILLING. The motive for this is
to be able to, move the so-referenced databases to another
server when I want to and reference that truely remote
server by the BILLING alias.
I have the alias set-up correctly and the server linked
via that alias with the proper security contexts.
When I query:
select * from [billing].master.dbo.sysdatabases
I get the resultset I want.
When I query:
begin tran
select * from [billing].master.dbo.sysdatabases
rollback tran
I get the following error:
Server: Msg 7391, Level 16, State 1, Line 2
The operation could not be performed because the OLE DB
provider 'SQLOLEDB' was unable to begin a distributed
transaction.
[OLE/DB provider returned message: New transaction cannot
enlist in the specified transaction coordinator. ]
OLE DB error trace [OLE/DB Provider 'SQLOLEDB'
ITransactionJoin::JoinTransaction returned 0x8004d00a].
If I use BILLING to alias another server (a truely remote
server), the transactioned query works without error.
I've came to understand this as a loopback linked server limitation
in that loopback linked servers cannot enlist in a distributed transaction.
But, I made a table, x, on sqlserver.Master with one int column, x
I made a stored proc, spx, on sqlserver.Master that takes one parameter
and inserts it's value into table x
On Sql Server I did the following
Use Master
go
if @.@.Trancount = 0 begin tran
exec [BILLING].Master.dbo.spx 1
select @.@.Trancount TranCount
if @.@.trancount != 0 commit tran
select * from [BILLING].Master.dbo.x
-- Saw 1 and no errors so transaction worked.
go
if @.@.Trancount = 0 begin tran
exec [BILLING].Master.dbo.spx 2
select @.@.Trancount TranCount
if @.@.trancount != 0 rollback tran
select * from [BILLING].Master.dbo.x
-- Saw 2 and no errors so transaction worked.
go
begin tran
select * from [BILLING].Master.dbo.x
-- Saw same error as cited above as expected.
if @.@.trancount != 0 rollback tran
What is going on? Transactions should have failed in stored proc usage
as well as a direct query if this were a loopback failure to enlist a
distributed transaction, shouldn't they?Hi
There are problems with loopbacks within implicit, explicit or distributed
transactions see http://tinyurl.com/5dlnq
John
"de_corum" <de_corum@.hotmail.com> wrote in message
news:unv3GUGiEHA.2880@.TK2MSFTNGP10.phx.gbl...
> I want to set a server up to be able to reference itself
> via an alias in a 4-part name. Let us call the server
> SQLSERVER and its alias BILLING. The motive for this is
> to be able to, move the so-referenced databases to another
> server when I want to and reference that truely remote
> server by the BILLING alias.
> I have the alias set-up correctly and the server linked
> via that alias with the proper security contexts.
> When I query:
> select * from [billing].master.dbo.sysdatabases
> I get the resultset I want.
> When I query:
> begin tran
> select * from [billing].master.dbo.sysdatabases
> rollback tran
> I get the following error:
> Server: Msg 7391, Level 16, State 1, Line 2
> The operation could not be performed because the OLE DB
> provider 'SQLOLEDB' was unable to begin a distributed
> transaction.
> [OLE/DB provider returned message: New transaction cannot
> enlist in the specified transaction coordinator. ]
> OLE DB error trace [OLE/DB Provider 'SQLOLEDB'
> ITransactionJoin::JoinTransaction returned 0x8004d00a].
> If I use BILLING to alias another server (a truely remote
> server), the transactioned query works without error.
> I've came to understand this as a loopback linked server limitation
> in that loopback linked servers cannot enlist in a distributed
transaction.
> But, I made a table, x, on sqlserver.Master with one int column, x
> I made a stored proc, spx, on sqlserver.Master that takes one parameter
> and inserts it's value into table x
> On Sql Server I did the following
> Use Master
> go
> if @.@.Trancount = 0 begin tran
> exec [BILLING].Master.dbo.spx 1
> select @.@.Trancount TranCount
> if @.@.trancount != 0 commit tran
> select * from [BILLING].Master.dbo.x
> -- Saw 1 and no errors so transaction worked.
> go
> if @.@.Trancount = 0 begin tran
> exec [BILLING].Master.dbo.spx 2
> select @.@.Trancount TranCount
> if @.@.trancount != 0 rollback tran
> select * from [BILLING].Master.dbo.x
> -- Saw 2 and no errors so transaction worked.
> go
> begin tran
> select * from [BILLING].Master.dbo.x
> -- Saw same error as cited above as expected.
> if @.@.trancount != 0 rollback tran
> What is going on? Transactions should have failed in stored proc usage
> as well as a direct query if this were a loopback failure to enlist a
> distributed transaction, shouldn't they?
>
>|||Ok, but why does it work when I am executing stored procs against the
loopback server and not when I am directly querying the tables?
"John Bell" <jbellnewsposts@.hotmail.com> wrote in message
news:ue4HnKHiEHA.3476@.tk2msftngp13.phx.gbl...
> Hi
> There are problems with loopbacks within implicit, explicit or distributed
> transactions see http://tinyurl.com/5dlnq
> John
> "de_corum" <de_corum@.hotmail.com> wrote in message
> news:unv3GUGiEHA.2880@.TK2MSFTNGP10.phx.gbl...
> transaction.
>