Friday, March 30, 2012

OPENQUERY vs 4-part-tablenames with linked server

Hi,
what is the difference between
a) select * from server.database.owner.table where [id] = 15
and
b) select * from openquery(server, 'select * from database.owner.table where [id] = 15')
I have the effect that b) gives the correct result while a) has zero hits.
Can anybody help?
Jochen
Jochen
That's strange. I hace just tested it on my box and it works fine
As far as I know when we use OPENQUERY SQL Server opens an addition connection to retrieve the data ( I am not sure for 100 percent)
"Jochen Brggemann" <brueggemann@.ifap.de> wrote in message news:udF3I4aXEHA.736@.TK2MSFTNGP10.phx.gbl...
Hi,
what is the difference between
a) select * from server.database.owner.table where [id] = 15
and
b) select * from openquery(server, 'select * from database.owner.table where [id] = 15')
I have the effect that b) gives the correct result while a) has zero hits.
Can anybody help?
Jochen
|||Jochen
That's strange. I hace just tested it on my box and it works fine
As far as I know when we use OPENQUERY SQL Server opens an addition connection to retrieve the data ( I am not sure for 100 percent)
"Jochen Brggemann" <brueggemann@.ifap.de> wrote in message news:udF3I4aXEHA.736@.TK2MSFTNGP10.phx.gbl...
Hi,
what is the difference between
a) select * from server.database.owner.table where [id] = 15
and
b) select * from openquery(server, 'select * from database.owner.table where [id] = 15')
I have the effect that b) gives the correct result while a) has zero hits.
Can anybody help?
Jochen
|||Here are some additional information:
SQL 2000 SP3 - Build 8.00.818
The database is merge replicated, but the effect is still there when I delete all replicational stuff.
Some more effects:
[id]-clumn has data from von 1 - 8000. With
select * from server.database.owner.table where [id] < 6000
the result table ist still empty. With
select * from server.database.owner.table where [id] < 6001
all rows are given back with [id] < 60001. Further it is strange that the server answers with correct results when I start the query on itsself (as whith OPENQUERY).
Jochen
"Uri Dimant" <urid@.iscar.co.il> schrieb im Newsbeitrag news:Os4al2bXEHA.2520@.TK2MSFTNGP12.phx.gbl...
Jochen
That's strange. I hace just tested it on my box and it works fine
As far as I know when we use OPENQUERY SQL Server opens an addition connection to retrieve the data ( I am not sure for 100 percent)
"Jochen Brggemann" <brueggemann@.ifap.de> wrote in message news:udF3I4aXEHA.736@.TK2MSFTNGP10.phx.gbl...
Hi,
what is the difference between
a) select * from server.database.owner.table where [id] = 15
and
b) select * from openquery(server, 'select * from database.owner.table where [id] = 15')
I have the effect that b) gives the correct result while a) has zero hits.
Can anybody help?
Jochen
|||Here are some additional information:
SQL 2000 SP3 - Build 8.00.818
The database is merge replicated, but the effect is still there when I delete all replicational stuff.
Some more effects:
[id]-clumn has data from von 1 - 8000. With
select * from server.database.owner.table where [id] < 6000
the result table ist still empty. With
select * from server.database.owner.table where [id] < 6001
all rows are given back with [id] < 60001. Further it is strange that the server answers with correct results when I start the query on itsself (as whith OPENQUERY).
Jochen
"Uri Dimant" <urid@.iscar.co.il> schrieb im Newsbeitrag news:Os4al2bXEHA.2520@.TK2MSFTNGP12.phx.gbl...
Jochen
That's strange. I hace just tested it on my box and it works fine
As far as I know when we use OPENQUERY SQL Server opens an addition connection to retrieve the data ( I am not sure for 100 percent)
"Jochen Brggemann" <brueggemann@.ifap.de> wrote in message news:udF3I4aXEHA.736@.TK2MSFTNGP10.phx.gbl...
Hi,
what is the difference between
a) select * from server.database.owner.table where [id] = 15
and
b) select * from openquery(server, 'select * from database.owner.table where [id] = 15')
I have the effect that b) gives the correct result while a) has zero hits.
Can anybody help?
Jochen
|||OPENQUERY allow you to control exactly what is passed to the other DBMS. I suggest you use showplan
to see what is submitted to the other DBMS in both cases...
Tibor Karaszi, SQL Server MVP
http://www.karaszi.com/sqlserver/default.asp
http://www.solidqualitylearning.com/
"Jochen Brggemann" <brueggemann@.ifap.de> wrote in message
news:udF3I4aXEHA.736@.TK2MSFTNGP10.phx.gbl...
Hi,
what is the difference between
a) select * from server.database.owner.table where [id] = 15
and
b) select * from openquery(server, 'select * from database.owner.table where [id] = 15')
I have the effect that b) gives the correct result while a) has zero hits.
Can anybody help?
Jochen
|||OPENQUERY allow you to control exactly what is passed to the other DBMS. I suggest you use showplan
to see what is submitted to the other DBMS in both cases...
Tibor Karaszi, SQL Server MVP
http://www.karaszi.com/sqlserver/default.asp
http://www.solidqualitylearning.com/
"Jochen Brggemann" <brueggemann@.ifap.de> wrote in message
news:udF3I4aXEHA.736@.TK2MSFTNGP10.phx.gbl...
Hi,
what is the difference between
a) select * from server.database.owner.table where [id] = 15
and
b) select * from openquery(server, 'select * from database.owner.table where [id] = 15')
I have the effect that b) gives the correct result while a) has zero hits.
Can anybody help?
Jochen
|||In this case OPENQUERY should return the same result as the straight query...
Do as Tibor says, and check the query plan for both to see if you can learn anything from that...Also check/play with the collation order options on the linked server(although that should not matter with an integer comparison.)
Wayne Snyder, MCDBA, SQL Server MVP
Mariner, Charlotte, NC
www.mariner-usa.com
(Please respond only to the newsgroups.)
I support the Professional Association of SQL Server (PASS) and it's
community of SQL Server professionals.
www.sqlpass.org
"Jochen Brggemann" <brueggemann@.ifap.de> wrote in message news:udF3I4aXEHA.736@.TK2MSFTNGP10.phx.gbl...
Hi,
what is the difference between
a) select * from server.database.owner.table where [id] = 15
and
b) select * from openquery(server, 'select * from database.owner.table where [id] = 15')
I have the effect that b) gives the correct result while a) has zero hits.
Can anybody help?
Jochen
|||In this case OPENQUERY should return the same result as the straight query...
Do as Tibor says, and check the query plan for both to see if you can learn anything from that...Also check/play with the collation order options on the linked server(although that should not matter with an integer comparison.)
Wayne Snyder, MCDBA, SQL Server MVP
Mariner, Charlotte, NC
www.mariner-usa.com
(Please respond only to the newsgroups.)
I support the Professional Association of SQL Server (PASS) and it's
community of SQL Server professionals.
www.sqlpass.org
"Jochen Brggemann" <brueggemann@.ifap.de> wrote in message news:udF3I4aXEHA.736@.TK2MSFTNGP10.phx.gbl...
Hi,
what is the difference between
a) select * from server.database.owner.table where [id] = 15
and
b) select * from openquery(server, 'select * from database.owner.table where [id] = 15')
I have the effect that b) gives the correct result while a) has zero hits.
Can anybody help?
Jochen

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