Does RAISERROR cause performance to go down slightly?

I was curious if using RAISERROR in the catch block of a stored procedure does actually causes some hit on performance? I think it would, as compared to simply returning an error code in this sp's output parameter.

It will cause some impact as RAISEERROR will inevitably require some extra resource, where as you rightly say an error code just requires a value to be set within an existing block of memory.

Does NEWID() affect my insert performance?

I have a SQL script, which is run during installation, as I want a
particular table to be populated initially. For this particular table I
have around 4000 recs that need to be populated. The script first
deletes all the rows in the table by the following statement:
Delete from [dbo].[Table1]
GO
Then there are 4000 following insert statement is as follows:
INSERT INTO [dbo].[Table1]
(Field1, Field2,Field3,Field4,Field5,Field6,Field7)
VALUES
(NEWID(),'0', '0', 'Test text','User1',GETDATE(),'Test Text')
GO
Since I have started using this script, my installer takes considerably
more time ....I cannot do a bulk insert using CSV because I am using
NEWID().
Is there a workaround?
Thanks.
"Pratham" <pratham17@.gmail.com> wrote in message
news:1144101429.666024.8280@.z34g2000cwc.googlegrou ps.com...
>I have a SQL script, which is run during installation, as I want a
> particular table to be populated initially. For this particular table I
> have around 4000 recs that need to be populated. The script first
> deletes all the rows in the table by the following statement:
> Delete from [dbo].[Table1]
> GO
> Then there are 4000 following insert statement is as follows:
> INSERT INTO [dbo].[Table1]
> (Field1, Field2,Field3,Field4,Field5,Field6,Field7)
> VALUES
> (NEWID(),'0', '0', 'Test text','User1',GETDATE(),'Test Text')
> GO
> Since I have started using this script, my installer takes considerably
> more time ....I cannot do a bulk insert using CSV because I am using
> NEWID().
> Is there a workaround?
>
The problem with using NEWID() like this is that the values are very
unordered, and so the index inserts get scattered all over. SQL Server 2005
introduces NEWSEQUENTIALID() to address this problem.
http://msdn2.microsoft.com/en-us/library/ms189786.aspx
But 4000 isn't a ton of rows in any case, and should take less than 10
seconds either way.
David
|||Thanks David, But I am using SQL 2000. Does anyone know, a way to do
this without changing the schema of the table?
Thanks
|||I agree with David that there should be no noticeable difference using
NEWID() with only 4000 rows. You mentioned that your installer takes
considerably longer but are you certain that it is this script that is the
cause?
Hope this helps.
Dan Guzman
SQL Server MVP
"Pratham" <pratham17@.gmail.com> wrote in message
news:1144101429.666024.8280@.z34g2000cwc.googlegrou ps.com...
>I have a SQL script, which is run during installation, as I want a
> particular table to be populated initially. For this particular table I
> have around 4000 recs that need to be populated. The script first
> deletes all the rows in the table by the following statement:
> Delete from [dbo].[Table1]
> GO
> Then there are 4000 following insert statement is as follows:
> INSERT INTO [dbo].[Table1]
> (Field1, Field2,Field3,Field4,Field5,Field6,Field7)
> VALUES
> (NEWID(),'0', '0', 'Test text','User1',GETDATE(),'Test Text')
> GO
> Since I have started using this script, my installer takes considerably
> more time ....I cannot do a bulk insert using CSV because I am using
> NEWID().
> Is there a workaround?
> Thanks.
>
|||You're change is probably because you are doing single inserts instead of
bulk insert. You might see if doing a truncate instead of delete buys you
enough to get your performance back.
This posting is provided "AS IS" with no warranties, and confers no rights.
Use of included script samples are subject to the terms specified at
http://www.microsoft.com/info/cpyright.htm
"Pratham" <pratham17@.gmail.com> wrote in message
news:1144101429.666024.8280@.z34g2000cwc.googlegrou ps.com...
>I have a SQL script, which is run during installation, as I want a
> particular table to be populated initially. For this particular table I
> have around 4000 recs that need to be populated. The script first
> deletes all the rows in the table by the following statement:
> Delete from [dbo].[Table1]
> GO
> Then there are 4000 following insert statement is as follows:
> INSERT INTO [dbo].[Table1]
> (Field1, Field2,Field3,Field4,Field5,Field6,Field7)
> VALUES
> (NEWID(),'0', '0', 'Test text','User1',GETDATE(),'Test Text')
> GO
> Since I have started using this script, my installer takes considerably
> more time ....I cannot do a bulk insert using CSV because I am using
> NEWID().
> Is there a workaround?
> Thanks.
>

Does NEWID() affect my insert performance?

I have a SQL script, which is run during installation, as I want a
particular table to be populated initially. For this particular table I
have around 4000 recs that need to be populated. The script first
deletes all the rows in the table by the following statement:
Delete from [dbo].[Table1]
GO
Then there are 4000 following insert statement is as follows:
INSERT INTO [dbo].[Table1]
(Field1, Field2,Field3,Field4,Field5,Field6,Field
7)
VALUES
(NEWID(),'0', '0', 'Test text','User1',GETDATE(),'Test Text')
GO
Since I have started using this script, my installer takes considerably
more time ....I cannot do a bulk insert using CSV because I am using
NEWID().
Is there a workaround?
Thanks."Pratham" <pratham17@.gmail.com> wrote in message
news:1144101429.666024.8280@.z34g2000cwc.googlegroups.com...
>I have a SQL script, which is run during installation, as I want a
> particular table to be populated initially. For this particular table I
> have around 4000 recs that need to be populated. The script first
> deletes all the rows in the table by the following statement:
> Delete from [dbo].[Table1]
> GO
> Then there are 4000 following insert statement is as follows:
> INSERT INTO [dbo].[Table1]
> (Field1, Field2,Field3,Field4,Field5,Field6,Field
7)
> VALUES
> (NEWID(),'0', '0', 'Test text','User1',GETDATE(),'Test Text')
> GO
> Since I have started using this script, my installer takes considerably
> more time ....I cannot do a bulk insert using CSV because I am using
> NEWID().
> Is there a workaround?
>
The problem with using NEWID() like this is that the values are very
unordered, and so the index inserts get scattered all over. SQL Server 2005
introduces NEWSEQUENTIALID() to address this problem.
http://msdn2.microsoft.com/en-us/library/ms189786.aspx
But 4000 isn't a ton of rows in any case, and should take less than 10
seconds either way.
David|||Thanks David, But I am using SQL 2000. Does anyone know, a way to do
this without changing the schema of the table?
Thanks|||I agree with David that there should be no noticeable difference using
NEWID() with only 4000 rows. You mentioned that your installer takes
considerably longer but are you certain that it is this script that is the
cause?
Hope this helps.
Dan Guzman
SQL Server MVP
"Pratham" <pratham17@.gmail.com> wrote in message
news:1144101429.666024.8280@.z34g2000cwc.googlegroups.com...
>I have a SQL script, which is run during installation, as I want a
> particular table to be populated initially. For this particular table I
> have around 4000 recs that need to be populated. The script first
> deletes all the rows in the table by the following statement:
> Delete from [dbo].[Table1]
> GO
> Then there are 4000 following insert statement is as follows:
> INSERT INTO [dbo].[Table1]
> (Field1, Field2,Field3,Field4,Field5,Field6,Field
7)
> VALUES
> (NEWID(),'0', '0', 'Test text','User1',GETDATE(),'Test Text')
> GO
> Since I have started using this script, my installer takes considerably
> more time ....I cannot do a bulk insert using CSV because I am using
> NEWID().
> Is there a workaround?
> Thanks.
>|||You're change is probably because you are doing single inserts instead of
bulk insert. You might see if doing a truncate instead of delete buys you
enough to get your performance back.
This posting is provided "AS IS" with no warranties, and confers no rights.
Use of included script samples are subject to the terms specified at
http://www.microsoft.com/info/cpyright.htm
"Pratham" <pratham17@.gmail.com> wrote in message
news:1144101429.666024.8280@.z34g2000cwc.googlegroups.com...
>I have a SQL script, which is run during installation, as I want a
> particular table to be populated initially. For this particular table I
> have around 4000 recs that need to be populated. The script first
> deletes all the rows in the table by the following statement:
> Delete from [dbo].[Table1]
> GO
> Then there are 4000 following insert statement is as follows:
> INSERT INTO [dbo].[Table1]
> (Field1, Field2,Field3,Field4,Field5,Field6,Field
7)
> VALUES
> (NEWID(),'0', '0', 'Test text','User1',GETDATE(),'Test Text')
> GO
> Since I have started using this script, my installer takes considerably
> more time ....I cannot do a bulk insert using CSV because I am using
> NEWID().
> Is there a workaround?
> Thanks.
>

Does NEWID() affect my insert performance?

I have a SQL script, which is run during installation, as I want a
particular table to be populated initially. For this particular table I
have around 4000 recs that need to be populated. The script first
deletes all the rows in the table by the following statement:
Delete from [dbo].[Table1]
GO
Then there are 4000 following insert statement is as follows:
INSERT INTO [dbo].[Table1]
(Field1, Field2,Field3,Field4,Field5,Field6,Field7)
VALUES
(NEWID(),'0', '0', 'Test text','User1',GETDATE(),'Test Text')
GO
Since I have started using this script, my installer takes considerably
more time ....I cannot do a bulk insert using CSV because I am using
NEWID().
Is there a workaround?
Thanks."Pratham" <pratham17@.gmail.com> wrote in message
news:1144101429.666024.8280@.z34g2000cwc.googlegroups.com...
>I have a SQL script, which is run during installation, as I want a
> particular table to be populated initially. For this particular table I
> have around 4000 recs that need to be populated. The script first
> deletes all the rows in the table by the following statement:
> Delete from [dbo].[Table1]
> GO
> Then there are 4000 following insert statement is as follows:
> INSERT INTO [dbo].[Table1]
> (Field1, Field2,Field3,Field4,Field5,Field6,Field7)
> VALUES
> (NEWID(),'0', '0', 'Test text','User1',GETDATE(),'Test Text')
> GO
> Since I have started using this script, my installer takes considerably
> more time ....I cannot do a bulk insert using CSV because I am using
> NEWID().
> Is there a workaround?
>
The problem with using NEWID() like this is that the values are very
unordered, and so the index inserts get scattered all over. SQL Server 2005
introduces NEWSEQUENTIALID() to address this problem.
http://msdn2.microsoft.com/en-us/library/ms189786.aspx
But 4000 isn't a ton of rows in any case, and should take less than 10
seconds either way.
David|||Thanks David, But I am using SQL 2000. Does anyone know, a way to do
this without changing the schema of the table?
Thanks|||I agree with David that there should be no noticeable difference using
NEWID() with only 4000 rows. You mentioned that your installer takes
considerably longer but are you certain that it is this script that is the
cause?
--
Hope this helps.
Dan Guzman
SQL Server MVP
"Pratham" <pratham17@.gmail.com> wrote in message
news:1144101429.666024.8280@.z34g2000cwc.googlegroups.com...
>I have a SQL script, which is run during installation, as I want a
> particular table to be populated initially. For this particular table I
> have around 4000 recs that need to be populated. The script first
> deletes all the rows in the table by the following statement:
> Delete from [dbo].[Table1]
> GO
> Then there are 4000 following insert statement is as follows:
> INSERT INTO [dbo].[Table1]
> (Field1, Field2,Field3,Field4,Field5,Field6,Field7)
> VALUES
> (NEWID(),'0', '0', 'Test text','User1',GETDATE(),'Test Text')
> GO
> Since I have started using this script, my installer takes considerably
> more time ....I cannot do a bulk insert using CSV because I am using
> NEWID().
> Is there a workaround?
> Thanks.
>|||You're change is probably because you are doing single inserts instead of
bulk insert. You might see if doing a truncate instead of delete buys you
enough to get your performance back.
--
This posting is provided "AS IS" with no warranties, and confers no rights.
Use of included script samples are subject to the terms specified at
http://www.microsoft.com/info/cpyright.htm
"Pratham" <pratham17@.gmail.com> wrote in message
news:1144101429.666024.8280@.z34g2000cwc.googlegroups.com...
>I have a SQL script, which is run during installation, as I want a
> particular table to be populated initially. For this particular table I
> have around 4000 recs that need to be populated. The script first
> deletes all the rows in the table by the following statement:
> Delete from [dbo].[Table1]
> GO
> Then there are 4000 following insert statement is as follows:
> INSERT INTO [dbo].[Table1]
> (Field1, Field2,Field3,Field4,Field5,Field6,Field7)
> VALUES
> (NEWID(),'0', '0', 'Test text','User1',GETDATE(),'Test Text')
> GO
> Since I have started using this script, my installer takes considerably
> more time ....I cannot do a bulk insert using CSV because I am using
> NEWID().
> Is there a workaround?
> Thanks.
>

Does MS know SQL2005 query performance is slower than SQL2000?

Hi,

I tested a simple query like Select colA from TableB where colC= 'XX' with SQL2000 and SQL2005.

Of course, Index is same, number of records are same.

After I execute that query and checked it with profiler. SQL2000 just took 18 ms but SQL2005 took 118 ms in my environment. Actually, the machine that is installed SQL2005 has better H/W spec than SQL2000.

I could not belive that so I tested several times but SQL2005 was slow.

After I searched this forum, I found that some guys had same problem with SQL2005 performance. I rebuilt index in SQL2005 but didn't work.

Even though I am using SP2, it is still slow than SQL2000.

Am I missing somthing? I could not understand how it could happen.

Does anybody have any solution?

Thank you in advance

James

did you clear the proc cache before running the procedures? Running the commands below will ensure that you are running both sprocs on common ground:

DBCC DROPCLEANBUFFERS
DBCC FREEPROCCACHE

Also, you can't always go by the time it takes to run a query. You really need to compare the logical reads returned by running the command SET STATISTICS IO ON before you run the statements to compare the reads. If your reads are drastically different, something may be funky.

Tim|||

Tim,

Thank you for answer.

Actually, before I tested, I restarted all services so it was not a problem of cache.

In addition, reads in profile log of SQL2005 is more than SQL2000 which is not strange based on the result.

Funny thing is speed is smiliar after data is cached. This problem happened when I tried data from disk.

I am not sure what is wrong.

I should discuss it with MS support soon.

Thank you

James

|||After you upgraded the database to SQL 2005 did you update the stats or rebuild the indexes? It's recommended to update the stats on the tables and indexes after upgrading to SQL 2005 to get proper query plans in SQL 2005.|||

Thank you Denny for replying

Unfortunately, it didn't work

Actually, I didn't migrate DB from SQL2000. I just created exactly same DB as SQL2000.

100ms is not a big deal for a SQL statement but if a stored procedure has 1000 sql statements. It will be 100,000ms which is a big.

This can explain why same stored procedure is slower than SQL2000.

James.

|||

Try optimising the data disks:

1) Set the disk to Basic disk

2) If the disk subsystem is RAID, set the stripe size to 64k, and the controller cache to 100% write.

3) Using DISKPART, create the partition using the command CREATE PARTITION PRIMARY ALIGN=64

4) Format the data disk with a cluster size of 64k.

Now you're ready to go from the disk side of things!

|||Does the execution plans show the SQL Servers taking the same path to the data? Where do the cost differences show up?|||

Danny and BigE

Thank you for replying.

Well. Execution plan is exactly same. I am not sure where it comes from.

As I said the machine that has SQL2005 is better H/W spec so I don't think it is a problem of H/W as BigE said.

I might try to do as BigE suggested but I could not agree we should set this for running SQL2005.

Think about that. SQL2005 is advanced version than SQL2000 which is 7 years ago!! Why does user consider about those kinds of disk setting? Even though it is ture, what is the big benefit of upgrading to user who is using small or medium application?

Anyway, If you have two machine that has SQL2000 and SQL2005, just try a select statement and check read and duration.

You will notice what I am saying..

James.|||

Hi James,

Did you get the solution as you described?

I have same problem and I cannot find any solutions.

Please help.

Clara

|||

Thank you BigE

I think your suggestion might improve performance but here is my concern about using SQL2005.

If it is a problem of Disk speed, Why does MS provide a fucntion to make DATABASE on top of the MEMORY DISK?

In other words, MS can create MEMORY DISK DATABASE in SQL2008 for better performance !

Maybe they will say to me that I am crazy but... If you can use UPS, then SQL server can dump that memory database to Disk during UPS is working.

Anyway, I could not buy that reason becaue , As I said, the SQL is running slower server than SQL2005.

By copying Clara,

Sorry, I could not find the solution yet. One of MS consultant that I know gave to me some suggestion but it doesn't work.

Maybe I should try SQL2008 CTP instead of SQL2005

Regards,

James Lim

Does MS know SQL2005 query performance is slower than SQL2000?

Hi,

I tested a simple query like Select colA from TableB where colC= 'XX' with SQL2000 and SQL2005.

Of course, Index is same, number of records are same.

After I execute that query and checked it with profiler. SQL2000 just took 18 ms but SQL2005 took 118 ms in my environment. Actually, the machine that is installed SQL2005 has better H/W spec than SQL2000.

I could not belive that so I tested several times but SQL2005 was slow.

After I searched this forum, I found that some guys had same problem with SQL2005 performance. I rebuilt index in SQL2005 but didn't work.

Even though I am using SP2, it is still slow than SQL2000.

Am I missing somthing? I could not understand how it could happen.

Does anybody have any solution?

Thank you in advance

James

did you clear the proc cache before running the procedures? Running the commands below will ensure that you are running both sprocs on common ground:

DBCC DROPCLEANBUFFERS
DBCC FREEPROCCACHE

Also, you can't always go by the time it takes to run a query. You really need to compare the logical reads returned by running the command SET STATISTICS IO ON before you run the statements to compare the reads. If your reads are drastically different, something may be funky.

Tim|||

Tim,

Thank you for answer.

Actually, before I tested, I restarted all services so it was not a problem of cache.

In addition, reads in profile log of SQL2005 is more than SQL2000 which is not strange based on the result.

Funny thing is speed is smiliar after data is cached. This problem happened when I tried data from disk.

I am not sure what is wrong.

I should discuss it with MS support soon.

Thank you

James

|||After you upgraded the database to SQL 2005 did you update the stats or rebuild the indexes? It's recommended to update the stats on the tables and indexes after upgrading to SQL 2005 to get proper query plans in SQL 2005.|||

Thank you Denny for replying

Unfortunately, it didn't work

Actually, I didn't migrate DB from SQL2000. I just created exactly same DB as SQL2000.

100ms is not a big deal for a SQL statement but if a stored procedure has 1000 sql statements. It will be 100,000ms which is a big.

This can explain why same stored procedure is slower than SQL2000.

James.

|||

Try optimising the data disks:

1) Set the disk to Basic disk

2) If the disk subsystem is RAID, set the stripe size to 64k, and the controller cache to 100% write.

3) Using DISKPART, create the partition using the command CREATE PARTITION PRIMARY ALIGN=64

4) Format the data disk with a cluster size of 64k.

Now you're ready to go from the disk side of things!

|||Does the execution plans show the SQL Servers taking the same path to the data? Where do the cost differences show up?|||

Danny and BigE

Thank you for replying.

Well. Execution plan is exactly same. I am not sure where it comes from.

As I said the machine that has SQL2005 is better H/W spec so I don't think it is a problem of H/W as BigE said.

I might try to do as BigE suggested but I could not agree we should set this for running SQL2005.

Think about that. SQL2005 is advanced version than SQL2000 which is 7 years ago!! Why does user consider about those kinds of disk setting? Even though it is ture, what is the big benefit of upgrading to user who is using small or medium application?

Anyway, If you have two machine that has SQL2000 and SQL2005, just try a select statement and check read and duration.

You will notice what I am saying..

James.|||

Hi James,

Did you get the solution as you described?

I have same problem and I cannot find any solutions.

Please help.

Clara

|||

Thank you BigE

I think your suggestion might improve performance but here is my concern about using SQL2005.

If it is a problem of Disk speed, Why does MS provide a fucntion to make DATABASE on top of the MEMORY DISK?

In other words, MS can create MEMORY DISK DATABASE in SQL2008 for better performance !

Maybe they will say to me that I am crazy but... If you can use UPS, then SQL server can dump that memory database to Disk during UPS is working.

Anyway, I could not buy that reason becaue , As I said, the SQL is running slower server than SQL2005.

By copying Clara,

Sorry, I could not find the solution yet. One of MS consultant that I know gave to me some suggestion but it doesn't work.

Maybe I should try SQL2008 CTP instead of SQL2005

Regards,

James Lim

Does MS know SQL2005 query performance is slower than SQL2000?

Hi,

I tested a simple query like Select colA from TableB where colC= 'XX' with SQL2000 and SQL2005.

Of course, Index is same, number of records are same.

After I execute that query and checked it with profiler. SQL2000 just took 18 ms but SQL2005 took 118 ms in my environment. Actually, the machine that is installed SQL2005 has better H/W spec than SQL2000.

I could not belive that so I tested several times but SQL2005 was slow.

After I searched this forum, I found that some guys had same problem with SQL2005 performance. I rebuilt index in SQL2005 but didn't work.

Even though I am using SP2, it is still slow than SQL2000.

Am I missing somthing? I could not understand how it could happen.

Does anybody have any solution?

Thank you in advance

James

did you clear the proc cache before running the procedures? Running the commands below will ensure that you are running both sprocs on common ground:

DBCC DROPCLEANBUFFERS
DBCC FREEPROCCACHE

Also, you can't always go by the time it takes to run a query. You really need to compare the logical reads returned by running the command SET STATISTICS IO ON before you run the statements to compare the reads. If your reads are drastically different, something may be funky.

Tim|||

Tim,

Thank you for answer.

Actually, before I tested, I restarted all services so it was not a problem of cache.

In addition, reads in profile log of SQL2005 is more than SQL2000 which is not strange based on the result.

Funny thing is speed is smiliar after data is cached. This problem happened when I tried data from disk.

I am not sure what is wrong.

I should discuss it with MS support soon.

Thank you

James

|||After you upgraded the database to SQL 2005 did you update the stats or rebuild the indexes? It's recommended to update the stats on the tables and indexes after upgrading to SQL 2005 to get proper query plans in SQL 2005.|||

Thank you Denny for replying

Unfortunately, it didn't work

Actually, I didn't migrate DB from SQL2000. I just created exactly same DB as SQL2000.

100ms is not a big deal for a SQL statement but if a stored procedure has 1000 sql statements. It will be 100,000ms which is a big.

This can explain why same stored procedure is slower than SQL2000.

James.

|||

Try optimising the data disks:

1) Set the disk to Basic disk

2) If the disk subsystem is RAID, set the stripe size to 64k, and the controller cache to 100% write.

3) Using DISKPART, create the partition using the command CREATE PARTITION PRIMARY ALIGN=64

4) Format the data disk with a cluster size of 64k.

Now you're ready to go from the disk side of things!

|||Does the execution plans show the SQL Servers taking the same path to the data? Where do the cost differences show up?|||

Danny and BigE

Thank you for replying.

Well. Execution plan is exactly same. I am not sure where it comes from.

As I said the machine that has SQL2005 is better H/W spec so I don't think it is a problem of H/W as BigE said.

I might try to do as BigE suggested but I could not agree we should set this for running SQL2005.

Think about that. SQL2005 is advanced version than SQL2000 which is 7 years ago!! Why does user consider about those kinds of disk setting? Even though it is ture, what is the big benefit of upgrading to user who is using small or medium application?

Anyway, If you have two machine that has SQL2000 and SQL2005, just try a select statement and check read and duration.

You will notice what I am saying..

James.|||

Hi James,

Did you get the solution as you described?

I have same problem and I cannot find any solutions.

Please help.

Clara

|||

Thank you BigE

I think your suggestion might improve performance but here is my concern about using SQL2005.

If it is a problem of Disk speed, Why does MS provide a fucntion to make DATABASE on top of the MEMORY DISK?

In other words, MS can create MEMORY DISK DATABASE in SQL2008 for better performance !

Maybe they will say to me that I am crazy but... If you can use UPS, then SQL server can dump that memory database to Disk during UPS is working.

Anyway, I could not buy that reason becaue , As I said, the SQL is running slower server than SQL2005.

By copying Clara,

Sorry, I could not find the solution yet. One of MS consultant that I know gave to me some suggestion but it doesn't work.

Maybe I should try SQL2008 CTP instead of SQL2005

Regards,

James Lim

does linked server solve performance issue??

Hi,
I've this query using four tables of 3 different databases residing on
the same server
select top 5 * from dblezen.dbo.ads ta
left outer join dbalgemeen.dbo.users tb on ta.ads_usrid = tb.usr_id
left outer join dbingeven.dbo.ads tc on ta.ads_ovid = tc.ads_adid
left outer join dbingeven.dbo.edition td on tc.ads_editionid = td.ed_id
where ta.ads_boonline > dateadd(n, -100, getdate())
In the near future we'll propably put the 3 databases on 3 different
physical servers. So I'll have to create linked servers, meaning I've
got to execute something like this :
select top 5 * from server1.dblezen.dbo.ads ta
left outer join server2.dbalgemeen.dbo.users tb on ta.ads_usrid = tb.usr_id
left outer join server3.dbingeven.dbo.ads tc on ta.ads_ovid = tc.ads_adid
left outer join server3.dbingeven.dbo.edition td on tc.ads_editionid =
td.ed_id
where ta.ads_boonline > dateadd(n, -100, getdate())
First question:
Can I fix that the servernames server1, server2 and server3 are logical
names (different than the computername) all refering to the same local
server?
If this is possible I guess I can adapt all my stored procedures before
effectively put the 3 databases on 3 different servers, and if
necessary, I can go back to 1 server again afterwards, without having to
change my stored procedures again.
Second question:
If it can be done, will it have consequences on the execution time of
the queries? Will there be overhead 1) because SQL server is going to
use distributed transaction instead of local transactions or 2) because
SQL server has to translate the logical server names into physical
server names while it's actually not necessary when the databases
reside on the same server.
Third question:
Is moving the 3 databases to 3 different servers and start using linked
server the obvious best option to resolve the performance problem of our
database server?
At the moment we have one IIS-server, running ASP.NET and one database
server, running SQL Server, using 3 databases.
- dbingeven is mainly used to insert new rows
- dblezen is mainly used to read rows (full text indexed)
- dbalgemeen contains general data used by the other two (user data,
parameters, statistical data, ...)
Data is continuously inserted in dbingeven and continuously copied
(after processing) to dblezen.
All 3 databases contain stored procedures refering each other all the
time (joins as in the query above as well as calling each others stored
procedures).
Fourth question:
Is it predictable the gain of performance win (on CPU, and disk access)
by spreading the data will be lost on network traffic and distributed
transactions processes, meaning our problem will not be really solved?
Thanks in Advance,
Peter Van Wilrijk.
Why don't you replicate the data back to the server that you're query is run
on, and select from there?
"Peter Van Wilrijk" <pro@.koopjeskrant.be> wrote in message
news:N_Vte.126388$I62.7018547@.phobos.telenet-ops.be...
> Hi,
> I've this query using four tables of 3 different databases residing on the
> same server
> select top 5 * from dblezen.dbo.ads ta
> left outer join dbalgemeen.dbo.users tb on ta.ads_usrid = tb.usr_id
> left outer join dbingeven.dbo.ads tc on ta.ads_ovid = tc.ads_adid
> left outer join dbingeven.dbo.edition td on tc.ads_editionid = td.ed_id
> where ta.ads_boonline > dateadd(n, -100, getdate())
> In the near future we'll propably put the 3 databases on 3 different
> physical servers. So I'll have to create linked servers, meaning I've
> got to execute something like this :
> select top 5 * from server1.dblezen.dbo.ads ta
> left outer join server2.dbalgemeen.dbo.users tb on ta.ads_usrid =
> tb.usr_id
> left outer join server3.dbingeven.dbo.ads tc on ta.ads_ovid = tc.ads_adid
> left outer join server3.dbingeven.dbo.edition td on tc.ads_editionid =
> td.ed_id
> where ta.ads_boonline > dateadd(n, -100, getdate())
> First question:
> Can I fix that the servernames server1, server2 and server3 are logical
> names (different than the computername) all refering to the same local
> server?
> If this is possible I guess I can adapt all my stored procedures before
> effectively put the 3 databases on 3 different servers, and if necessary,
> I can go back to 1 server again afterwards, without having to change my
> stored procedures again.
> Second question:
> If it can be done, will it have consequences on the execution time of the
> queries? Will there be overhead 1) because SQL server is going to use
> distributed transaction instead of local transactions or 2) because SQL
> server has to translate the logical server names into physical server
> names while it's actually not necessary when the databases
> reside on the same server.
> Third question:
> Is moving the 3 databases to 3 different servers and start using linked
> server the obvious best option to resolve the performance problem of our
> database server?
> At the moment we have one IIS-server, running ASP.NET and one database
> server, running SQL Server, using 3 databases.
> - dbingeven is mainly used to insert new rows
> - dblezen is mainly used to read rows (full text indexed)
> - dbalgemeen contains general data used by the other two (user data,
> parameters, statistical data, ...)
> Data is continuously inserted in dbingeven and continuously copied (after
> processing) to dblezen.
> All 3 databases contain stored procedures refering each other all the time
> (joins as in the query above as well as calling each others stored
> procedures).
> Fourth question:
> Is it predictable the gain of performance win (on CPU, and disk access)
> by spreading the data will be lost on network traffic and distributed
> transactions processes, meaning our problem will not be really solved?
>
> Thanks in Advance,
> Peter Van Wilrijk.
>
>
>
>
>
|||ChrisR wrote:
> Why don't you replicate the data back to the server that you're query is run
> on, and select from there?
>
Thanks, Good question?
I surely must start checking out how to implement replication ... but I
guess it will not be an option for our website, because our users, while
surfing ... read, insert and update data in all three databases. I
guess this means we should replicate continuously in two directions, so
updates, deletes and inserts on server 2 must be immediately available
on server 1 and vice versa. Can replication do that?
Kind regards,
Peter Roothans.
|||Yes. Look up Transactional Replication in BOL. You will want to use the
Immediate Updating option.
"Peter Van Wilrijk" <pro@.koopjeskrant.be> wrote in message
news:Tu9ue.126847$Xj7.7072901@.phobos.telenet-ops.be...
> ChrisR wrote:
> Thanks, Good question?
> I surely must start checking out how to implement replication ... but I
> guess it will not be an option for our website, because our users, while
> surfing ... read, insert and update data in all three databases. I guess
> this means we should replicate continuously in two directions, so updates,
> deletes and inserts on server 2 must be immediately available on server 1
> and vice versa. Can replication do that?
> Kind regards,
> Peter Roothans.
>
|||Thanks ChrisR.
I just found out you can give 1 server multiple names as follows.
sp_addlinkedserver N'SRVDBI', ' ', N'SQLOLEDB', N'SRV-WEBDB'
sp_addlinkedserver N'SRVDBL', ' ', N'SQLOLEDB', N'SRV-WEBDB'
sp_addlinkedserver N'SRVDBA', ' ', N'SQLOLEDB', N'SRV-WEBDB'
So, this way I can move my database to any server without the need to
adapt all code. The only thing to do than, is to let refer the logical
name to another physical server.
I've read BOL concerning Transactional Replication. I'm certainly going
to try it out, but since I'm not familiair with it and since the
document warns for loopback detection when replicating multiple related
databases, I'll start with the linked server solution.
Thanks,
Kind regards,
Peter Van Wilrijk
ChrisR wrote:
> Yes. Look up Transactional Replication in BOL. You will want to use the
> Immediate Updating option.
>
> "Peter Van Wilrijk" <pro@.koopjeskrant.be> wrote in message
> news:Tu9ue.126847$Xj7.7072901@.phobos.telenet-ops.be...
>
>

does linked server solve performance issue??

Hi,
I've this query using four tables of 3 different databases residing on
the same server
select top 5 * from dblezen.dbo.ads ta
left outer join dbalgemeen.dbo.users tb on ta.ads_usrid = tb.usr_id
left outer join dbingeven.dbo.ads tc on ta.ads_ovid = tc.ads_adid
left outer join dbingeven.dbo.edition td on tc.ads_editionid = td.ed_id
where ta.ads_boonline > dateadd(n, -100, getdate())
In the near future we'll propably put the 3 databases on 3 different
physical servers. So I'll have to create linked servers, meaning I've
got to execute something like this :
select top 5 * from server1.dblezen.dbo.ads ta
left outer join server2.dbalgemeen.dbo.users tb on ta.ads_usrid = tb.usr_id
left outer join server3.dbingeven.dbo.ads tc on ta.ads_ovid = tc.ads_adid
left outer join server3.dbingeven.dbo.edition td on tc.ads_editionid =
td.ed_id
where ta.ads_boonline > dateadd(n, -100, getdate())
First question:
Can I fix that the servernames server1, server2 and server3 are logical
names (different than the computername) all refering to the same local
server?
If this is possible I guess I can adapt all my stored procedures before
effectively put the 3 databases on 3 different servers, and if
necessary, I can go back to 1 server again afterwards, without having to
change my stored procedures again.
Second question:
If it can be done, will it have consequences on the execution time of
the queries? Will there be overhead 1) because SQL server is going to
use distributed transaction instead of local transactions or 2) because
SQL server has to translate the logical server names into physical
server names while it's actually not necessary when the databases
reside on the same server.
Third question:
Is moving the 3 databases to 3 different servers and start using linked
server the obvious best option to resolve the performance problem of our
database server'
At the moment we have one IIS-server, running ASP.NET and one database
server, running SQL Server, using 3 databases.
- dbingeven is mainly used to insert new rows
- dblezen is mainly used to read rows (full text indexed)
- dbalgemeen contains general data used by the other two (user data,
parameters, statistical data, ...)
Data is continuously inserted in dbingeven and continuously copied
(after processing) to dblezen.
All 3 databases contain stored procedures refering each other all the
time (joins as in the query above as well as calling each others stored
procedures).
Fourth question:
Is it predictable the gain of performance win (on CPU, and disk access)
by spreading the data will be lost on network traffic and distributed
transactions processes, meaning our problem will not be really solved'
Thanks in Advance,
Peter Van Wilrijk.Why don't you replicate the data back to the server that you're query is run
on, and select from there?
"Peter Van Wilrijk" <pro@.koopjeskrant.be> wrote in message
news:N_Vte.126388$I62.7018547@.phobos.telenet-ops.be...
> Hi,
> I've this query using four tables of 3 different databases residing on the
> same server
> select top 5 * from dblezen.dbo.ads ta
> left outer join dbalgemeen.dbo.users tb on ta.ads_usrid = tb.usr_id
> left outer join dbingeven.dbo.ads tc on ta.ads_ovid = tc.ads_adid
> left outer join dbingeven.dbo.edition td on tc.ads_editionid = td.ed_id
> where ta.ads_boonline > dateadd(n, -100, getdate())
> In the near future we'll propably put the 3 databases on 3 different
> physical servers. So I'll have to create linked servers, meaning I've
> got to execute something like this :
> select top 5 * from server1.dblezen.dbo.ads ta
> left outer join server2.dbalgemeen.dbo.users tb on ta.ads_usrid =
> tb.usr_id
> left outer join server3.dbingeven.dbo.ads tc on ta.ads_ovid = tc.ads_adid
> left outer join server3.dbingeven.dbo.edition td on tc.ads_editionid =
> td.ed_id
> where ta.ads_boonline > dateadd(n, -100, getdate())
> First question:
> Can I fix that the servernames server1, server2 and server3 are logical
> names (different than the computername) all refering to the same local
> server?
> If this is possible I guess I can adapt all my stored procedures before
> effectively put the 3 databases on 3 different servers, and if necessary,
> I can go back to 1 server again afterwards, without having to change my
> stored procedures again.
> Second question:
> If it can be done, will it have consequences on the execution time of the
> queries? Will there be overhead 1) because SQL server is going to use
> distributed transaction instead of local transactions or 2) because SQL
> server has to translate the logical server names into physical server
> names while it's actually not necessary when the databases
> reside on the same server.
> Third question:
> Is moving the 3 databases to 3 different servers and start using linked
> server the obvious best option to resolve the performance problem of our
> database server'
> At the moment we have one IIS-server, running ASP.NET and one database
> server, running SQL Server, using 3 databases.
> - dbingeven is mainly used to insert new rows
> - dblezen is mainly used to read rows (full text indexed)
> - dbalgemeen contains general data used by the other two (user data,
> parameters, statistical data, ...)
> Data is continuously inserted in dbingeven and continuously copied (after
> processing) to dblezen.
> All 3 databases contain stored procedures refering each other all the time
> (joins as in the query above as well as calling each others stored
> procedures).
> Fourth question:
> Is it predictable the gain of performance win (on CPU, and disk access)
> by spreading the data will be lost on network traffic and distributed
> transactions processes, meaning our problem will not be really solved'
>
> Thanks in Advance,
> Peter Van Wilrijk.
>
>
>
>
>|||ChrisR wrote:
> Why don't you replicate the data back to the server that you're query is r
un
> on, and select from there?
>
Thanks, Good question?
I surely must start checking out how to implement replication ... but I
guess it will not be an option for our website, because our users, while
surfing ... read, insert and update data in all three databases. I
guess this means we should replicate continuously in two directions, so
updates, deletes and inserts on server 2 must be immediately available
on server 1 and vice versa. Can replication do that?
Kind regards,
Peter Roothans.|||Yes. Look up Transactional Replication in BOL. You will want to use the
Immediate Updating option.
"Peter Van Wilrijk" <pro@.koopjeskrant.be> wrote in message
news:Tu9ue.126847$Xj7.7072901@.phobos.telenet-ops.be...
> ChrisR wrote:
> Thanks, Good question?
> I surely must start checking out how to implement replication ... but I
> guess it will not be an option for our website, because our users, while
> surfing ... read, insert and update data in all three databases. I guess
> this means we should replicate continuously in two directions, so updates,
> deletes and inserts on server 2 must be immediately available on server 1
> and vice versa. Can replication do that?
> Kind regards,
> Peter Roothans.
>|||Thanks ChrisR.
I just found out you can give 1 server multiple names as follows.
sp_addlinkedserver N'SRVDBI', ' ', N'SQLOLEDB', N'SRV-WEBDB'
sp_addlinkedserver N'SRVDBL', ' ', N'SQLOLEDB', N'SRV-WEBDB'
sp_addlinkedserver N'SRVDBA', ' ', N'SQLOLEDB', N'SRV-WEBDB'
So, this way I can move my database to any server without the need to
adapt all code. The only thing to do than, is to let refer the logical
name to another physical server.
I've read BOL concerning Transactional Replication. I'm certainly going
to try it out, but since I'm not familiair with it and since the
document warns for loopback detection when replicating multiple related
databases, I'll start with the linked server solution.
Thanks,
Kind regards,
Peter Van Wilrijk
ChrisR wrote:
> Yes. Look up Transactional Replication in BOL. You will want to use the
> Immediate Updating option.
>
> "Peter Van Wilrijk" <pro@.koopjeskrant.be> wrote in message
> news:Tu9ue.126847$Xj7.7072901@.phobos.telenet-ops.be...
>
>
>

does linked server solve performance issue??

Hi,
I've this query using four tables of 3 different databases residing on
the same server
select top 5 * from dblezen.dbo.ads ta
left outer join dbalgemeen.dbo.users tb on ta.ads_usrid = tb.usr_id
left outer join dbingeven.dbo.ads tc on ta.ads_ovid = tc.ads_adid
left outer join dbingeven.dbo.edition td on tc.ads_editionid = td.ed_id
where ta.ads_boonline > dateadd(n, -100, getdate())
In the near future we'll propably put the 3 databases on 3 different
physical servers. So I'll have to create linked servers, meaning I've
got to execute something like this :
select top 5 * from server1.dblezen.dbo.ads ta
left outer join server2.dbalgemeen.dbo.users tb on ta.ads_usrid = tb.usr_id
left outer join server3.dbingeven.dbo.ads tc on ta.ads_ovid = tc.ads_adid
left outer join server3.dbingeven.dbo.edition td on tc.ads_editionid = td.ed_id
where ta.ads_boonline > dateadd(n, -100, getdate())
First question:
Can I fix that the servernames server1, server2 and server3 are logical
names (different than the computername) all refering to the same local
server?
If this is possible I guess I can adapt all my stored procedures before
effectively put the 3 databases on 3 different servers, and if
necessary, I can go back to 1 server again afterwards, without having to
change my stored procedures again.
Second question:
If it can be done, will it have consequences on the execution time of
the queries? Will there be overhead 1) because SQL server is going to
use distributed transaction instead of local transactions or 2) because
SQL server has to translate the logical server names into physical
server names while it's actually not necessary when the databases
reside on the same server.
Third question:
Is moving the 3 databases to 3 different servers and start using linked
server the obvious best option to resolve the performance problem of our
database server'
At the moment we have one IIS-server, running ASP.NET and one database
server, running SQL Server, using 3 databases.
- dbingeven is mainly used to insert new rows
- dblezen is mainly used to read rows (full text indexed)
- dbalgemeen contains general data used by the other two (user data,
parameters, statistical data, ...)
Data is continuously inserted in dbingeven and continuously copied
(after processing) to dblezen.
All 3 databases contain stored procedures refering each other all the
time (joins as in the query above as well as calling each others stored
procedures).
Fourth question:
Is it predictable the gain of performance win (on CPU, and disk access)
by spreading the data will be lost on network traffic and distributed
transactions processes, meaning our problem will not be really solved'
Thanks in Advance,
Peter Van Wilrijk.Why don't you replicate the data back to the server that you're query is run
on, and select from there?
"Peter Van Wilrijk" <pro@.koopjeskrant.be> wrote in message
news:N_Vte.126388$I62.7018547@.phobos.telenet-ops.be...
> Hi,
> I've this query using four tables of 3 different databases residing on the
> same server
> select top 5 * from dblezen.dbo.ads ta
> left outer join dbalgemeen.dbo.users tb on ta.ads_usrid = tb.usr_id
> left outer join dbingeven.dbo.ads tc on ta.ads_ovid = tc.ads_adid
> left outer join dbingeven.dbo.edition td on tc.ads_editionid = td.ed_id
> where ta.ads_boonline > dateadd(n, -100, getdate())
> In the near future we'll propably put the 3 databases on 3 different
> physical servers. So I'll have to create linked servers, meaning I've
> got to execute something like this :
> select top 5 * from server1.dblezen.dbo.ads ta
> left outer join server2.dbalgemeen.dbo.users tb on ta.ads_usrid => tb.usr_id
> left outer join server3.dbingeven.dbo.ads tc on ta.ads_ovid = tc.ads_adid
> left outer join server3.dbingeven.dbo.edition td on tc.ads_editionid => td.ed_id
> where ta.ads_boonline > dateadd(n, -100, getdate())
> First question:
> Can I fix that the servernames server1, server2 and server3 are logical
> names (different than the computername) all refering to the same local
> server?
> If this is possible I guess I can adapt all my stored procedures before
> effectively put the 3 databases on 3 different servers, and if necessary,
> I can go back to 1 server again afterwards, without having to change my
> stored procedures again.
> Second question:
> If it can be done, will it have consequences on the execution time of the
> queries? Will there be overhead 1) because SQL server is going to use
> distributed transaction instead of local transactions or 2) because SQL
> server has to translate the logical server names into physical server
> names while it's actually not necessary when the databases
> reside on the same server.
> Third question:
> Is moving the 3 databases to 3 different servers and start using linked
> server the obvious best option to resolve the performance problem of our
> database server'
> At the moment we have one IIS-server, running ASP.NET and one database
> server, running SQL Server, using 3 databases.
> - dbingeven is mainly used to insert new rows
> - dblezen is mainly used to read rows (full text indexed)
> - dbalgemeen contains general data used by the other two (user data,
> parameters, statistical data, ...)
> Data is continuously inserted in dbingeven and continuously copied (after
> processing) to dblezen.
> All 3 databases contain stored procedures refering each other all the time
> (joins as in the query above as well as calling each others stored
> procedures).
> Fourth question:
> Is it predictable the gain of performance win (on CPU, and disk access)
> by spreading the data will be lost on network traffic and distributed
> transactions processes, meaning our problem will not be really solved'
>
> Thanks in Advance,
> Peter Van Wilrijk.
>
>
>
>
>|||ChrisR wrote:
> Why don't you replicate the data back to the server that you're query is run
> on, and select from there?
>
Thanks, Good question?
I surely must start checking out how to implement replication ... but I
guess it will not be an option for our website, because our users, while
surfing ... read, insert and update data in all three databases. I
guess this means we should replicate continuously in two directions, so
updates, deletes and inserts on server 2 must be immediately available
on server 1 and vice versa. Can replication do that?
Kind regards,
Peter Roothans.|||Yes. Look up Transactional Replication in BOL. You will want to use the
Immediate Updating option.
"Peter Van Wilrijk" <pro@.koopjeskrant.be> wrote in message
news:Tu9ue.126847$Xj7.7072901@.phobos.telenet-ops.be...
> ChrisR wrote:
>> Why don't you replicate the data back to the server that you're query is
>> run on, and select from there?
> Thanks, Good question?
> I surely must start checking out how to implement replication ... but I
> guess it will not be an option for our website, because our users, while
> surfing ... read, insert and update data in all three databases. I guess
> this means we should replicate continuously in two directions, so updates,
> deletes and inserts on server 2 must be immediately available on server 1
> and vice versa. Can replication do that?
> Kind regards,
> Peter Roothans.
>|||Thanks ChrisR.
I just found out you can give 1 server multiple names as follows.
sp_addlinkedserver N'SRVDBI', ' ', N'SQLOLEDB', N'SRV-WEBDB'
sp_addlinkedserver N'SRVDBL', ' ', N'SQLOLEDB', N'SRV-WEBDB'
sp_addlinkedserver N'SRVDBA', ' ', N'SQLOLEDB', N'SRV-WEBDB'
So, this way I can move my database to any server without the need to
adapt all code. The only thing to do than, is to let refer the logical
name to another physical server.
I've read BOL concerning Transactional Replication. I'm certainly going
to try it out, but since I'm not familiair with it and since the
document warns for loopback detection when replicating multiple related
databases, I'll start with the linked server solution.
Thanks,
Kind regards,
Peter Van Wilrijk
ChrisR wrote:
> Yes. Look up Transactional Replication in BOL. You will want to use the
> Immediate Updating option.
>
> "Peter Van Wilrijk" <pro@.koopjeskrant.be> wrote in message
> news:Tu9ue.126847$Xj7.7072901@.phobos.telenet-ops.be...
>>ChrisR wrote:
>>Why don't you replicate the data back to the server that you're query is
>>run on, and select from there?
>>
>>Thanks, Good question?
>>I surely must start checking out how to implement replication ... but I
>>guess it will not be an option for our website, because our users, while
>>surfing ... read, insert and update data in all three databases. I guess
>>this means we should replicate continuously in two directions, so updates,
>>deletes and inserts on server 2 must be immediately available on server 1
>>and vice versa. Can replication do that?
>>Kind regards,
>>Peter Roothans.
>
>

Does LIKE operator have major performance issue with variables?

Hi all,
Below are two similar SQL statements that give the same results:
1. SELECT * FROM InvoiceDtl WHERE IvoNum LIKE ('Ivo-0510-00001')
2. DECLARE @.IvoNum AS NVARCHAR (20)
SET @.IvoNum = 'Ivo-0510-00001'
SELECT * FROM InvoiceDtl WHERE IvoNum LIKE (@.IvoNum)
InvoiceDtl is a big table with 2.3++ million rows. IvoNum is of type
NVARCHAR (20) and has a non-clustered index.
I run both statements seperately in Query Analyzer. Statement 1 takes 1-2
seconds. But statement 2 takes 3-4 minutes (and makes my harddisk run mad)!
Cld anyone pls kindly advise why that is happening? TQ.SQL Server processes batches of SQL statements in 3 steps:
1) Parsing: check for invalid code
2) Compilation: generate an execution plan, which tables/indexes to use, and
the order to access them in etc
3) Execution: execute the execution plan generated in step 2
Now for the first statement SQL knows the value of IvoNum it has to look for
as early as step 2, because it is a literal. The Query optimizer can look up
statistics on the indexes and estimate how often the value 'Ivo-0510-00001'
appears in the column IvoNum, and generate the fastest execution plan to be
executed by step 3.
For the second statement, SQL Server does NOT know the value of IvoNum it
has to look as early as step 2. @.IvoNum is a variable, at the assignment of
a value to this variable only happens during execution in step 3. If T-SQL
had constants, you could declare @.IvoNum as a constant, and the value would
be available in step 2, but T-SQL only has variables not constants. So the
Query Optimizer does not know in step 2 to as to what the value of @.IvoNum
will be during execution. So it uses an estimate for the number of rows that
might match, and IIRC, that estimate is 30%. Remember that the value of
@.IvoNum is unknown during step 2, so it might be 'Ivo-0510-00001' , 'Ivo%'
'%0510-00001' or even '%' in step 3. This estimate leads to a very different
execution plan, which in cases will include scanning all 2.3 million rows in
the table.
Jacco Schalkwijk
SQL Server MVP
"HardKhor" <HardKhor@.discussions.microsoft.com> wrote in message
news:43932C3C-D0D8-42EE-AE09-7388DBA8D6CE@.microsoft.com...
> Hi all,
> Below are two similar SQL statements that give the same results:
> 1. SELECT * FROM InvoiceDtl WHERE IvoNum LIKE ('Ivo-0510-00001')
> 2. DECLARE @.IvoNum AS NVARCHAR (20)
> SET @.IvoNum = 'Ivo-0510-00001'
> SELECT * FROM InvoiceDtl WHERE IvoNum LIKE (@.IvoNum)
> InvoiceDtl is a big table with 2.3++ million rows. IvoNum is of type
> NVARCHAR (20) and has a non-clustered index.
> I run both statements seperately in Query Analyzer. Statement 1 takes 1-2
> seconds. But statement 2 takes 3-4 minutes (and makes my harddisk run
> mad)!
> Cld anyone pls kindly advise why that is happening? TQ.|||HardKhor,
I got some questions for you here...
1) Why do you have nvarchar as datatype here? wouldnt varchar or char be
better?
2) Why 20 chars at most? If 'Ivo-0510-00001' is the longest, why not
char(14) ?
3) Why use LIKE if 'Ivo-0510-00001' is an exact match? i.e ... WHERE
Something='Ivo-0510-00001'
/Lasse
"HardKhor" <HardKhor@.discussions.microsoft.com> wrote in message
news:43932C3C-D0D8-42EE-AE09-7388DBA8D6CE@.microsoft.com...
> Hi all,
> Below are two similar SQL statements that give the same results:
> 1. SELECT * FROM InvoiceDtl WHERE IvoNum LIKE ('Ivo-0510-00001')
> 2. DECLARE @.IvoNum AS NVARCHAR (20)
> SET @.IvoNum = 'Ivo-0510-00001'
> SELECT * FROM InvoiceDtl WHERE IvoNum LIKE (@.IvoNum)
> InvoiceDtl is a big table with 2.3++ million rows. IvoNum is of type
> NVARCHAR (20) and has a non-clustered index.
> I run both statements seperately in Query Analyzer. Statement 1 takes 1-2
> seconds. But statement 2 takes 3-4 minutes (and makes my harddisk run
mad)!
> Cld anyone pls kindly advise why that is happening? TQ.

Does JOINs and VIEWs lose performance when used with more than one DataBase?

Hi,
My application consist of 2 big parts, which work together but are in some
way seperate.
In case I should store the 2 parts in different databases (but on the same
server), will I lose performance when doing a query that joins tables from
both databases? And what about views?
Any help our hints would be really appreciated.
Thanks a lot in advance,
Pieter
On Fri, 4 Nov 2005 17:59:02 +0100, Pieter wrote:

> Hi,
> My application consist of 2 big parts, which work together but are in some
> way seperate.
> In case I should store the 2 parts in different databases (but on the same
> server), will I lose performance when doing a query that joins tables from
> both databases? And what about views?
> Any help our hints would be really appreciated.
> Thanks a lot in advance,
> Pieter
Hello,
You will have no performance decrease. Try to always include the owner in
the object naming (dbo I hope), to ease the work of SQL Server.
What you physically loose splitting your model, is of course the DRIs, but
you can manage it with triggers.
Rudi Bruchez
MCDBA
|||ok! thanks a lot!
"Rudi Bruchez" <rudi#no-spam#at.babaluga.com> wrote in message
news:1goqk59i7hqzp$.146q0p9y2vigx$.dlg@.40tude.net. ..
> On Fri, 4 Nov 2005 17:59:02 +0100, Pieter wrote:
>
> Hello,
> You will have no performance decrease. Try to always include the owner in
> the object naming (dbo I hope), to ease the work of SQL Server.
> What you physically loose splitting your model, is of course the DRIs, but
> you can manage it with triggers.
> --
> Rudi Bruchez
> MCDBA

Does JOINs and VIEWs lose performance when used with more than one DataBase?

Hi,
My application consist of 2 big parts, which work together but are in some
way seperate.
In case I should store the 2 parts in different databases (but on the same
server), will I lose performance when doing a query that joins tables from
both databases? And what about views?
Any help our hints would be really appreciated.
Thanks a lot in advance,
PieterOn Fri, 4 Nov 2005 17:59:02 +0100, Pieter wrote:

> Hi,
> My application consist of 2 big parts, which work together but are in some
> way seperate.
> In case I should store the 2 parts in different databases (but on the same
> server), will I lose performance when doing a query that joins tables from
> both databases? And what about views?
> Any help our hints would be really appreciated.
> Thanks a lot in advance,
> Pieter
Hello,
You will have no performance decrease. Try to always include the owner in
the object naming (dbo I hope), to ease the work of SQL Server.
What you physically loose splitting your model, is of course the DRIs, but
you can manage it with triggers.
Rudi Bruchez
MCDBA|||ok! thanks a lot!
"Rudi Bruchez" <rudi#no-spam#at.babaluga.com> wrote in message
news:1goqk59i7hqzp$.146q0p9y2vigx$.dlg@.40tude.net...
> On Fri, 4 Nov 2005 17:59:02 +0100, Pieter wrote:
>
> Hello,
> You will have no performance decrease. Try to always include the owner in
> the object naming (dbo I hope), to ease the work of SQL Server.
> What you physically loose splitting your model, is of course the DRIs, but
> you can manage it with triggers.
> --
> Rudi Bruchez
> MCDBA

Does JOINs and VIEWs lose performance when used with more than one DataBase?

Hi,
My application consist of 2 big parts, which work together but are in some
way seperate.
In case I should store the 2 parts in different databases (but on the same
server), will I lose performance when doing a query that joins tables from
both databases? And what about views?
Any help our hints would be really appreciated.
Thanks a lot in advance,
PieterOn Fri, 4 Nov 2005 17:59:02 +0100, Pieter wrote:
> Hi,
> My application consist of 2 big parts, which work together but are in some
> way seperate.
> In case I should store the 2 parts in different databases (but on the same
> server), will I lose performance when doing a query that joins tables from
> both databases? And what about views?
> Any help our hints would be really appreciated.
> Thanks a lot in advance,
> Pieter
Hello,
You will have no performance decrease. Try to always include the owner in
the object naming (dbo I hope), to ease the work of SQL Server.
What you physically loose splitting your model, is of course the DRIs, but
you can manage it with triggers.
--
Rudi Bruchez
MCDBA|||ok! thanks a lot!
"Rudi Bruchez" <rudi#no-spam#at.babaluga.com> wrote in message
news:1goqk59i7hqzp$.146q0p9y2vigx$.dlg@.40tude.net...
> On Fri, 4 Nov 2005 17:59:02 +0100, Pieter wrote:
>> Hi,
>> My application consist of 2 big parts, which work together but are in
>> some
>> way seperate.
>> In case I should store the 2 parts in different databases (but on the
>> same
>> server), will I lose performance when doing a query that joins tables
>> from
>> both databases? And what about views?
>> Any help our hints would be really appreciated.
>> Thanks a lot in advance,
>> Pieter
> Hello,
> You will have no performance decrease. Try to always include the owner in
> the object naming (dbo I hope), to ease the work of SQL Server.
> What you physically loose splitting your model, is of course the DRIs, but
> you can manage it with triggers.
> --
> Rudi Bruchez
> MCDBA

Does it increase performance to use multiple datafiles for large databases

If you've large databases (above 200GB/file). Does it help to have multiple smaller files (For e.g four 50GB files)? Does it improve performance. Also if a single table (size 200gb) is alloted to a file group which has one datafile. Does it help to have such filegroup with multiple files (fore e.g 4 files of 50GB each). My thought was if SQL Server is looking for certain data (assuming the file is not very fragmented) it is better for SQL Server to load up only the specific file that corresponds to the data, instead of loading up an entire 200gb file.

Moving to engine forum|||In general, the size of the data files does not really matter that much, as SQL Server will not load an entire file. SQL Server uses an offset in a file to go to a particular page (8K chunk of data) that it needs to load.

What really matters is the placement of files on disks, and the type of disks you use. If you have a single large file that is backed up by a RAID array, it does not really matter much. However, if you use ordinary (non-RAID) disks, multiple files might help, as you can place different files on different disk. Especially, placing the non-clustered indexes on different disks than clustered indexes will help.

Also, placing tempdb on (one or more) different disks, and placing the log files on different disks will help performance.

If you need more information, could you explain the problem you are trying to solve in a litte bit more detail.

Thanks,

Marcel van der Holst
[MSFT]|||

A lot of this depends on what kind of storage you have, whether is direct attached storage or a SAN, and if its a SAN, what kind of SAN it is. Generally speaking, Microsoft recommends that you have one TempDB file per physical CPU (and dual-core CPUs count as physical CPUs here), and one data file for each physical CPU. Doing this can help with allocation bottlenecks. Some SANs (such as 3PAR) make this somewhat moot, since they spread a file among all of the physical disks. Having multiple small data files can make backups and restores easier to manage.

You want your data files on one set of disks, log files on another set of disks, and TempDB on another set of disks.

Does it increase performance to use multiple datafiles for large databases

If you've large databases (above 200GB/file). Does it help to have multiple smaller files (For e.g four 50GB files)? Does it improve performance. Also if a single table (size 200gb) is alloted to a file group which has one datafile. Does it help to have such filegroup with multiple files (fore e.g 4 files of 50GB each). My thought was if SQL Server is looking for certain data (assuming the file is not very fragmented) it is better for SQL Server to load up only the specific file that corresponds to the data, instead of loading up an entire 200gb file.

Moving to engine forum|||In general, the size of the data files does not really matter that much, as SQL Server will not load an entire file. SQL Server uses an offset in a file to go to a particular page (8K chunk of data) that it needs to load.

What really matters is the placement of files on disks, and the type of disks you use. If you have a single large file that is backed up by a RAID array, it does not really matter much. However, if you use ordinary (non-RAID) disks, multiple files might help, as you can place different files on different disk. Especially, placing the non-clustered indexes on different disks than clustered indexes will help.

Also, placing tempdb on (one or more) different disks, and placing the log files on different disks will help performance.

If you need more information, could you explain the problem you are trying to solve in a litte bit more detail.

Thanks,

Marcel van der Holst
[MSFT]|||

A lot of this depends on what kind of storage you have, whether is direct attached storage or a SAN, and if its a SAN, what kind of SAN it is. Generally speaking, Microsoft recommends that you have one TempDB file per physical CPU (and dual-core CPUs count as physical CPUs here), and one data file for each physical CPU. Doing this can help with allocation bottlenecks. Some SANs (such as 3PAR) make this somewhat moot, since they spread a file among all of the physical disks. Having multiple small data files can make backups and restores easier to manage.

You want your data files on one set of disks, log files on another set of disks, and TempDB on another set of disks.

Does it effect performance to have several publications instead of just 1. to the same sub

for example:
I am publishing about 5 tables to one subscriber.
Each table is approx 10gb each. I want to break
them up into 5 different publications in case
something happens to one of them and I need to
reinitialize. I figure If i had to , it would
only need to reinitialize that 1 10gb table.
Whereas if I had all 5 in one publication I would
then be reinitilizing all 5 10gb tables instead
of doing just one.
Am I causing more work for my distributor? I
figured it wouldn't hurt since it's the same log
reader for all the publications and same
distribution agent as well.
tia
-comb
Absolutely not!
In general when deploying very large snapshots like this you should
investigate
compressing your snapshots
bcping the data into the file system and then into the tables
Or using a DTS package with the fast insert option - this provides the best
performance.
Doing this on a live environment will require validation and some clean up
work to ensure everything is in sync.
You will get better performance by using multiple distribution agents if you
use the independent option. I find that using two agents works best. Most
than two causes performance degradation a the pull subscriber. Your results
may vary.
"Combfilter" <adsf@.asdf.com> wrote in message
news:MPG.1be892207facc1cc9896cf@.news.newsreader.co m...
> for example:
> I am publishing about 5 tables to one subscriber.
> Each table is approx 10gb each. I want to break
> them up into 5 different publications in case
> something happens to one of them and I need to
> reinitialize. I figure If i had to , it would
> only need to reinitialize that 1 10gb table.
> Whereas if I had all 5 in one publication I would
> then be reinitilizing all 5 10gb tables instead
> of doing just one.
> Am I causing more work for my distributor? I
> figured it wouldn't hurt since it's the same log
> reader for all the publications and same
> distribution agent as well.
> tia
> -comb
|||In article <OdRqiZ7uEHA.3972
@.TK2MSFTNGP15.phx.gbl>, hilary.cotter@.gmail.com
says...
> Absolutely not!
> In general when deploying very large snapshots like this you should
> investigate
> compressing your snapshots
> bcping the data into the file system and then into the tables
> Or using a DTS package with the fast insert option - this provides the best
> performance.
> Doing this on a live environment will require validation and some clean up
> work to ensure everything is in sync.
> You will get better performance by using multiple distribution agents if you
> use the independent option. I find that using two agents works best. Most
> than two causes performance degradation a the pull subscriber. Your results
> may vary.
>
> "Combfilter" <adsf@.asdf.com> wrote in message
> news:MPG.1be892207facc1cc9896cf@.news.newsreader.co m...
>
>
Thanks Hilary.
I see how to compress the snapshots, but then
when i read some of the older group discussions
about that , that it takes a lot of time to
decompress on the subscriber side and really
doesn't seem to be faster. I would like to learn
how to find a faster way to get these snapshots
over to the subscriber and have them sync up, but
I am not that skilled at sql. I have read some
of your and pauls notes about doing a backup of
the db and restore on the subscriber and some how
you can setup replication "with no sync" or
something like that but cannot find any how to
articles on how to do this.
thanks,
comb
|||In general a compressed snapshot will travel across the wire faster than an
uncompressed on, but then you will have to wait for the snapshot to be
extracted. I have found that the snapshot files I have worked with extract
relatively quickly and compress quickly as well.
I think you should bcp your data into the file system, compress them, send
them across the wire and then bcp them in. Do a no sync subscription and a
validation. Then you need to play catch up to get your subscriber in sync
with the publisher.
If you need more details post back here and Paul or myself will help you.
Hilary Cotter
Looking for a SQL Server replication book?
http://www.nwsu.com/0974973602.html
"Combfilter" <adsf@.asdf.com> wrote in message
news:MPG.1be979f3afe5a3769896d0@.news.newsreader.co m...[vbcol=seagreen]
> In article <OdRqiZ7uEHA.3972
> @.TK2MSFTNGP15.phx.gbl>, hilary.cotter@.gmail.com
> says...
best[vbcol=seagreen]
up[vbcol=seagreen]
you[vbcol=seagreen]
Most[vbcol=seagreen]
results
> Thanks Hilary.
> I see how to compress the snapshots, but then
> when i read some of the older group discussions
> about that , that it takes a lot of time to
> decompress on the subscriber side and really
> doesn't seem to be faster. I would like to learn
> how to find a faster way to get these snapshots
> over to the subscriber and have them sync up, but
> I am not that skilled at sql. I have read some
> of your and pauls notes about doing a backup of
> the db and restore on the subscriber and some how
> you can setup replication "with no sync" or
> something like that but cannot find any how to
> articles on how to do this.
> thanks,
> comb
|||In article <#WIdSMJvEHA.1300
@.TK2MSFTNGP14.phx.gbl>, hilary.cotter@.gmail.com
says...
> In general a compressed snapshot will travel across the wire faster than an
> uncompressed on, but then you will have to wait for the snapshot to be
> extracted. I have found that the snapshot files I have worked with extract
> relatively quickly and compress quickly as well.
> I think you should bcp your data into the file system, compress them, send
> them across the wire and then bcp them in. Do a no sync subscription and a
> validation. Then you need to play catch up to get your subscriber in sync
> with the publisher.
> If you need more details post back here and Paul or myself will help you.
>
I tried the compression method yesterday, but my
snapshot agent went suspect. I am guessing when
you say use bcp method that just means click the
check box that says "compress snapshot" under
snapshotlocation tab in the publication
properties? I saw it create a bcp file , and
then once that file was there the next step it
started was to add it to a .cab file, so I am
assuming that was correct? Not sure why my agent
went suspect.
Where do I find the no sync option? Will this
hurt me in the long run? I've searched google
groups and google up and down for a site that
will show this step by step.
Thanks for yours and pauls help in this group.
comb

Does High Duration and Low CPU = IO problems?

I have several queries that have a high duration (3,000 ms) and much lower
CPU values (300 ms). Is this ALWAYS an indicator of IO performance problems,
or could it be indicating other factors as well?>> On 11/27/2006 at 9:58 AM, in message
<ABFCA63C-E4D6-44B2-AECD-B8435E5F12E2@.microsoft.com>,
Dan<Dan@.discussions.microsoft.com> wrote:
> I have several queries that have a high duration (3,000 ms) and much
> lower
> CPU values (300 ms). Is this ALWAYS an indicator of IO performance
> problems,
> or could it be indicating other factors as well?
It could be other factors. For instance, a machine that is swapping or
has too little memory would do this too.|||What would be the next steps in diagnosis?
"Joel Maslak" wrote:
> >> On 11/27/2006 at 9:58 AM, in message
> <ABFCA63C-E4D6-44B2-AECD-B8435E5F12E2@.microsoft.com>,
> Dan<Dan@.discussions.microsoft.com> wrote:
> > I have several queries that have a high duration (3,000 ms) and much
> > lower
> > CPU values (300 ms). Is this ALWAYS an indicator of IO performance
> > problems,
> > or could it be indicating other factors as well?
>
> It could be other factors. For instance, a machine that is swapping or
> has too little memory would do this too.
>|||It is possible that the query is being blocked by another process. Also,
that query could be used by an app that does much work between retrieving
each row. The duration includes the time it takes to retrieve the last row.
--
Tom
----
Thomas A. Moreau, BSc, PhD, MCSE, MCDBA, MCITP, MCTS
SQL Server MVP
Toronto, ON Canada
.
"Dan" <Dan@.discussions.microsoft.com> wrote in message
news:ABFCA63C-E4D6-44B2-AECD-B8435E5F12E2@.microsoft.com...
I have several queries that have a high duration (3,000 ms) and much lower
CPU values (300 ms). Is this ALWAYS an indicator of IO performance problems,
or could it be indicating other factors as well?|||In addition to Tom's suggestions, check out the execution plans and see if you can better them
(re-writing queries, adding indexes and all that jazz).
--
Tibor Karaszi, SQL Server MVP
http://www.karaszi.com/sqlserver/default.asp
http://www.solidqualitylearning.com/
"Dan" <Dan@.discussions.microsoft.com> wrote in message
news:D8D6F9E9-7C45-4778-A5DF-B9E911D55768@.microsoft.com...
> What would be the next steps in diagnosis?
> "Joel Maslak" wrote:
>> >> On 11/27/2006 at 9:58 AM, in message
>> <ABFCA63C-E4D6-44B2-AECD-B8435E5F12E2@.microsoft.com>,
>> Dan<Dan@.discussions.microsoft.com> wrote:
>> > I have several queries that have a high duration (3,000 ms) and much
>> > lower
>> > CPU values (300 ms). Is this ALWAYS an indicator of IO performance
>> > problems,
>> > or could it be indicating other factors as well?
>>
>> It could be other factors. For instance, a machine that is swapping or
>> has too little memory would do this too.

Does High Duration and Low CPU = IO problems?

I have several queries that have a high duration (3,000 ms) and much lower
CPU values (300 ms). Is this ALWAYS an indicator of IO performance problems,
or could it be indicating other factors as well?
>>> On 11/27/2006 at 9:58 AM, in message
<ABFCA63C-E4D6-44B2-AECD-B8435E5F12E2@.microsoft.com>,
Dan<Dan@.discussions.microsoft.com> wrote:
> I have several queries that have a high duration (3,000 ms) and much
> lower
> CPU values (300 ms). Is this ALWAYS an indicator of IO performance
> problems,
> or could it be indicating other factors as well?
It could be other factors. For instance, a machine that is swapping or
has too little memory would do this too.
|||What would be the next steps in diagnosis?
"Joel Maslak" wrote:

> <ABFCA63C-E4D6-44B2-AECD-B8435E5F12E2@.microsoft.com>,
> Dan<Dan@.discussions.microsoft.com> wrote:
>
> It could be other factors. For instance, a machine that is swapping or
> has too little memory would do this too.
>
|||It is possible that the query is being blocked by another process. Also,
that query could be used by an app that does much work between retrieving
each row. The duration includes the time it takes to retrieve the last row.
Tom
Thomas A. Moreau, BSc, PhD, MCSE, MCDBA, MCITP, MCTS
SQL Server MVP
Toronto, ON Canada
..
"Dan" <Dan@.discussions.microsoft.com> wrote in message
news:ABFCA63C-E4D6-44B2-AECD-B8435E5F12E2@.microsoft.com...
I have several queries that have a high duration (3,000 ms) and much lower
CPU values (300 ms). Is this ALWAYS an indicator of IO performance problems,
or could it be indicating other factors as well?

Does High Duration and Low CPU = IO problems?

I have several queries that have a high duration (3,000 ms) and much lower
CPU values (300 ms). Is this ALWAYS an indicator of IO performance problems,
or could it be indicating other factors as well?>>> On 11/27/2006 at 9:58 AM, in message
<ABFCA63C-E4D6-44B2-AECD-B8435E5F12E2@.microsoft.com>,
Dan<Dan@.discussions.microsoft.com> wrote:
> I have several queries that have a high duration (3,000 ms) and much
> lower
> CPU values (300 ms). Is this ALWAYS an indicator of IO performance
> problems,
> or could it be indicating other factors as well?
It could be other factors. For instance, a machine that is swapping or
has too little memory would do this too.|||What would be the next steps in diagnosis?
"Joel Maslak" wrote:

> <ABFCA63C-E4D6-44B2-AECD-B8435E5F12E2@.microsoft.com>,
> Dan<Dan@.discussions.microsoft.com> wrote:
>
> It could be other factors. For instance, a machine that is swapping or
> has too little memory would do this too.
>|||It is possible that the query is being blocked by another process. Also,
that query could be used by an app that does much work between retrieving
each row. The duration includes the time it takes to retrieve the last row.
Tom
----
Thomas A. Moreau, BSc, PhD, MCSE, MCDBA, MCITP, MCTS
SQL Server MVP
Toronto, ON Canada
.
"Dan" <Dan@.discussions.microsoft.com> wrote in message
news:ABFCA63C-E4D6-44B2-AECD-B8435E5F12E2@.microsoft.com...
I have several queries that have a high duration (3,000 ms) and much lower
CPU values (300 ms). Is this ALWAYS an indicator of IO performance problems,
or could it be indicating other factors as well?|||In addition to Tom's suggestions, check out the execution plans and see if y
ou can better them
(re-writing queries, adding indexes and all that jazz).
Tibor Karaszi, SQL Server MVP
http://www.karaszi.com/sqlserver/default.asp
http://www.solidqualitylearning.com/
"Dan" <Dan@.discussions.microsoft.com> wrote in message
news:D8D6F9E9-7C45-4778-A5DF-B9E911D55768@.microsoft.com...[vbcol=seagreen]
> What would be the next steps in diagnosis?
> "Joel Maslak" wrote:
>