Extremely Poor Query Performance - Identical DBs Different Performance

Jun 23, 2006

Hello Everyone,

I have a very complex performance issue with our production database.
Here's the scenario. We have a production webserver server and a
development web server. Both are running SQL Server 2000.

I encounted various performance issues with the production server with a
particular query. It would take approximately 22 seconds to return 100
rows, thats about 0.22 seconds per row. Note: I ran the query in single
user mode. So I tested the query on the Development server by taking a
backup (.dmp) of the database and moving it onto the dev server. I ran
the same query and found that it ran in less than a second.

I took a look at the query execution plan and I found that they we're
the exact same in both cases.

Then I took a look at the various index's, and again I found no
differences in the table indices.

If both databases are identical, I'm assumeing that the issue is related
to some external hardware issue like: disk space, memory etc. Or could
it be OS software related issues, like service packs, SQL Server
configuations etc.

Here's what I've done to rule out some obvious hardware issues on the
prod server:
1. Moved all extraneous files to a secondary harddrive to free up space
on the primary harddrive. There is 55gb's of free space on the disk.
2. Applied SQL Server SP4 service packs
3. Defragmented the primary harddrive
4. Applied all Windows Server 2003 updates


Here is the prod servers system specs:
2x Intel Xeon 2.67GHZ
Total Physical Memory 2GB, Available Physical Memory 815MB
Windows Server 2003 SE /w SP1

Here is the dev serers system specs:
2x Intel Xeon 2.80GHz
2GB DDR2-SDRAM
Windows Server 2003 SE /w SP1

I'm not sure what else to do, the query performance is an order of
magnitude difference and I can't explain it. To me its is a hardware or
operating system related issue.

Any Ideas would help me greatly!

Thanks,
Brian T

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Very Poor Performance - Identical DBs But Different Performance

Jun 22, 2006

Hello Everyone,I have a very complex performance issue with our production database.Here's the scenario. We have a production webserver server and adevelopment web server. Both are running SQL Server 2000.I encounted various performance issues with the production server witha particular query. It would take approximately 22 seconds to return100 rows, thats about 0.22 seconds per row. Note: I ran the query insingle user mode. So I tested the query on the Development server bytaking a backup (.dmp) of the database and moving it onto the devserver. I ran the same query and found that it ran in less than asecond.I took a look at the query execution plan and I found that they we'rethe exact same in both cases.Then I took a look at the various index's, and again I found nodifferences in the table indices.If both databases are identical, I'm assumeing that the issue isrelated to some external hardware issue like: disk space, memory etc.Or could it be OS software related issues, like service packs, SQLServer configuations etc.Here's what I've done to rule out some obvious hardware issues on theprod server:1. Moved all extraneous files to a secondary harddrive to free up spaceon the primary harddrive. There is 55gb's of free space on the disk.2. Applied SQL Server SP4 service packs3. Defragmented the primary harddrive4. Applied all Windows Server 2003 updatesHere is the prod servers system specs:2x Intel Xeon 2.67GHZTotal Physical Memory 2GB, Available Physical Memory 815MBWindows Server 2003 SE /w SP1Here is the dev serers system specs:2x Intel Xeon 2.80GHz2GB DDR2-SDRAMWindows Server 2003 SE /w SP1I'm not sure what else to do, the query performance is an order ofmagnitude difference and I can't explain it. To me its is a hardware oroperating systemrelated issue.Any Ideas would help me greatly!Thanks,Brian T

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May 1, 2006

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Is there anything I can do to increase performance?
Are there any options other than the OLE DB Command to perform updates?

Thank you.

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Apr 4, 2000

Hi,
I have just upgrade my sql 6.5 to 7.0 version. This sql box (compaq proliant 5500) has 1 gig ram and 4 pentium pro processors and smart array controller. There are about 200 users hit on that server constantly. I configured this server according compaq white paper and Microsoft recommendation; however, I am still suffering huge performance hit. Then I setup performance monitor to see what is happening. What I see is all of 4 processors are at 70% processor time constantly. What I heard is sql 7.0 runs much better on pentium III processors. Is that true? Or you have any recommendations??


Help!!
Thanks!!

Jim Zhong

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Sep 24, 2007

Hi

I have the following structure:

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This is my problem:

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I would like to know what problem can be cause this delay.

Thanks

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Feb 4, 2008

Is there a way to improve this query?
The execution plan states that it's ,aking use of the Indexes as 'Clustered Index Seeks'
but the query takes 30 minutes to complete.
The Index statistics are also up to date!
If I use just an INNER JOIN the query completes in 2 seconds!
How can I make the LEFT OUTER JOIN more optimal?
SELECT A.MeterSerial AS 'PeaceMeter', B.MeterFrom, B.MeterTo,
CASE WHEN A.MeterSerial = B.MeterFrom
OR A.MeterSerial = B.MeterTo
OR A.MeterSerial BETWEEN B.MeterFrom AND B.MeterTo
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FROM Peace.MeterData_DR1 A LEFT OUTER JOIN
(SELECT MeterFrom, MeterTo, ComplexMeterType
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Hi,I am having a problem with one of my stored procedures in SQL Server 2005.  Basically the proc brings back a data set for the ASP.NET front end, but it is running very slowly from .NET. I have run SQL profiler on the procedure and its taking around 20 seconds to bring back the data for the .NET, where as if I copy and paste the executed SP from profiler into the management studio and run it in a query window, it runs in around 1 second, even if I run DBCC DROPCLEANBUFFERS before I run it.  More worryingly, the CPU usage is 40 times higher and the number of reads is 50% higher from .NET.We have the .NET front end spread over 3 clustered web servers with load balancers and the SQL db is on a dedicated rig.  I am having the same problem on my locally published version of the site as well, so I don't think it's an issue with the web site.If anyone has got any ideas on this then please let me know as I am completely stuck.  I should mention that the issue has only recently started occuring and it used to be fine and the rest of the site is fine...Thanks in advance Tom    

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Hi,

I created a cube in my development box, tested, performance is great, now if I try to deploy it into the production server from VS, the screen freezes without any error msg... after some time playing around with security I gave up and created a backup of the cube, and sent it over to the IT department( I have no direct control over the production server so they restored the cube ). Now with the cube in production, it was a matter of just processing it... well that didn't go well either... it would take forever from my development box to see results... then I tried to browse any dimension using the data already on the backup... a simple 4 values dimension would take 2-4 minutes to load on screen...

I can't understand why browsing the cube its so slow in the production server, IT admin even reported that when trying to browse locally it would be slow too... The server has 16gbs of RAM and its a dual processor, he didnt notice any lack of CPU or memory while browsing the cube...

Have you experienced this or can you help me troubleshoot whats going on?

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We just converted from SQL Server 2000 to SQL SERVER 2005 and it seems as though we are having trouble with our performance. Sets of queries that used to take about 15 seconds now take almost 2 minutes. We used a utility to find out what was taking so long and found that almost all of the wait time belonged to LCK_M_S. Does anyone have any suggestions?

Here is a snippet of code I used to test the speed against 2000:

declare @counter int
set @counter = 1

while @counter < 200
BEGIN
update UPR40500 set actindx = 96 where actindx = 96
set @counter = @counter+1
END

This takes 15 seconds when it used to take virtually no time at all.

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Poor Index Performance

Mar 24, 2007

Hey guys,

Having some trouble with indexes on sql server 2005. I'll explain it with a simplified example.
I have a customers table, and a sp to list customers :


create table Customers(
CusID int not null,
Name varchar(50) null,
Surname varchar(50) null,
CusNo int not null,
Deleted bit not null
)


create proc spCusLs (
@CusID int = null,
@Name varchar(50) = null,
@Surname varchar(50) = null,
@CusNo int = null
)
as

select
CusID,
Name,
Surname,
CusNo
from
Customers
where
Deleted = 0
and CusID <> 1000
and (@CusID is null or CusID = @CusID)
and (@CusNo is null or CusNo = @CusNo)
and (@Name is null or Name like @Name)
and (@Surname is null or Surname like @Surname)
order by
Name,
Surname


create nonclustered index ix_customers_name on customers ([name] asc)
with (sort_in_tempdb = off, drop_existing = off, ignore_dup_key = off, online = off) on primary

create nonclustered index ix_customers_surname on customers (surname asc)
with (sort_in_tempdb = off, drop_existing = off, ignore_dup_key = off, online = off) on primary

create nonclustered index ix_customers_cusno on customers (cusno asc)
with (sort_in_tempdb = off, drop_existing = off, ignore_dup_key = off, online = off) on primary



I've recently noticed that some tables, including 'Customers' don't have indexes except primary keys. And I have added indexes to "name", "surname" and "cusno" columns. This has dropped the number of IO reads. But the strange thing is; one time it works with name / surname searches like ('joh%' '%') but when CusNo is included, it does a full scan. And vice versa when the SP is recompiled using 'alter', works ok with CusNo, but not with name/surname. Recompile it, and it's reversed again. When run as a single query, the execution plan looks different.

What's happening? Perhaps something to do with statistics? This doesn't have a big payload on the server, but there are some other procs suffering from this on heavy queries, making server performance worse than before...

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Poor Performance On Oracle

Aug 3, 2006

Attention: To all SSIS gods like Donald Farmer, Jamie Thompson, Michael Entin

I am so very disappointed with the performance of SSIS on Oracle. When I am doing a simple lookup, it is caching the entire lookup table that is killing my performance. What is worst? When I try to change from Full to Partial or None caching mode, the component throws an error (x) sign.

I am also so frustrated with the way I have warnings all over the place. The warnings are saying code page value for the column cannot be determined. But the code page value is defaulted to 1252. I looked around everywhere to find what the damn code page value of my Oracle database is without any luck.

The damn package that I created takes 10 minutes to process 10,000 records ONLY which is slower than a legacy Cognos Decision Stream!!! Unacceptable!!! My lookup tables on an average have 200,000 records and I DO NOT WANT TO CACHE THEM all for 10,000 records. Something seems messed up!!!

PLEASE HELP!!!!!!!!!!!!!!!!!!!!!!!

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Jan 10, 2006

Using a query through a linked server is giving tremendously reduced performance.
Is part of the problem linking from a SQL 2000 to a SQL 7.0 database?
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Thanks.

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Mar 31, 2008

i need to select data by using a very complex sql statement. when i use a ole db source componente and choose SQL command as data access mode the process never ends. but when i put the sql statement in an sql task component it works fine and fast. isn't an oledb source always based on an sql statement (select *)? so how is it possible that this component becomes so slow?

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Poor Performance On Sql 2005 Vs. Sql 2000 - AGAIN!

May 15, 2008

I was hoping I wouldn't be another poster with performance issues after migrating to SQl 2005 from SQL 2000 but here I am.

I am in the process of testing out our databases on Sql Server 2005 for migration from SQL Server 2000 and there are certain portions of code that have been affected negatively. I have read thru many of the posts here and have tried out most of the recommendations. I will start out with things I've done and then provide the actual SQL.

1) I have rebuilt all indexes ( using the DBCC REINDEX using the table option).
2) Updated the db engine to latest hot fix (build 3239) that addresses speed related fixes.
3) I also ran sp_createstats using the 'fullscan' option to create stats on all columns of all tables (minus indexed columns)
4) Since nothing seemed to work, I even ran UPDATE STATICS with FULL SCAN on all tables even though I did not need it as the REBUILD woudl have created stats. But I was willing to try anything.

I have confirmed that the execution plans are different even though the data on both sql 2000 and sql 2005 are identical (i put a copy on 2005). The plans themselves are huge as the queries are huge. Here is the query.


SELECT InterimView.* ,TestView.*

FROM View_LabDataExport_TestFormData_55 TestView
RIGHT OUTER JOIN ( SELECT ReqView.*, CDView.*
FROM View_LabDataExport_FormData_55 ReqView
LEFT OUTER JOIN View_LabDataExport_FormData_CD_55 CDView
ON ( CDView.DB_SubjectID_CD = ReqView.DB_SUbjectID )

) InterimView

ON ( InterimView.DB_FormID = TestView.DB_FormID_T AND

InterimView.DB_LabSampleID = TestView.DB_LabSampleID_T )

The above query takes abotu 8 secs to run on 2000 and about 1 minute to run on 2005. This is for a small dataset and on larger datasets this is only going to more pronounced ( as confirmed by other teams that have already migrated in my company). Another point worth mentioning might be if I remove the TestView.* from the select list, it works in 5 to 6 seconds. Is there an issue with Sql 2005 and a large number of columns or anything of that sort? On 2000, the time remains the same , about 8 seconds if I remove this from the select list.

Here is the statistics ion on 2005


(21234 row(s) affected)

Table 'Worktable'. Scan count 75490, logical reads 3676867, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

Table 'LabTestToReportPanel'. Scan count 476, logical reads 1524, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

Table 'LabReportPanel'. Scan count 0, logical reads 260, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

Table 'DiscreteValue'. Scan count 1, logical reads 176106, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

Table 'LabReleasedSampleTest'. Scan count 1, logical reads 2078, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

Table 'LabSample'. Scan count 1360, logical reads 18567, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

Table 'Form'. Scan count 2302, logical reads 8225, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

Table 'LabTest'. Scan count 1, logical reads 23, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

Table 'LabSampleDef'. Scan count 1, logical reads 10530, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

Table 'LabArea'. Scan count 1, logical reads 2, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

Table 'Lab'. Scan count 1, logical reads 2, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

Table 'Location'. Scan count 1, logical reads 2, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

Table 'Study'. Scan count 0, logical reads 6, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

Table 'Item'. Scan count 1335, logical reads 32940, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

Table 'ObjectState'. Scan count 1, logical reads 10972, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

Table 'Object'. Scan count 0, logical reads 20674, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

Table 'Subject'. Scan count 0, logical reads 3293, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

Table 'FormDef'. Scan count 2, logical reads 70, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

Table 'PrintedLabSampleLabel'. Scan count 0, logical reads 13144, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

Table 'PrintedForm'. Scan count 0, logical reads 4219, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

Table 'StudySite'. Scan count 0, logical reads 2756, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

Table 'StudyEvent'. Scan count 18, logical reads 40, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

Table 'StudyEventDef'. Scan count 0, logical reads 36, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

Table 'FormDefToStudyEventDef'. Scan count 1, logical reads 43, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

Table 'LabSampleDefToFormDef'. Scan count 1, logical reads 255, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.

Here is the statistics ion on 2000

Table 'LabTestToReportPanel'. Scan count 2123, logical reads 4820, physical reads 44, read-ahead reads 0.

Table 'LabReportPanel'. Scan count 130, logical reads 260, physical reads 0, read-ahead reads 0.

Table 'DiscreteValue'. Scan count 103914, logical reads 208214, physical reads 0, read-ahead reads 0.

Table 'Location'. Scan count 19031, logical reads 38062, physical reads 2, read-ahead reads 0.

Table 'Lab'. Scan count 19031, logical reads 38062, physical reads 0, read-ahead reads 0.

Table 'LabArea'. Scan count 19031, logical reads 38062, physical reads 0, read-ahead reads 0.

Table 'LabSampleDef'. Scan count 24670, logical reads 49340, physical reads 0, read-ahead reads 0.

Table 'LabTest'. Scan count 19406, logical reads 39575, physical reads 0, read-ahead reads 0.

Table 'LabReleasedSampleTest'. Scan count 4289, logical reads 73865, physical reads 1014, read-ahead reads 24.

Table 'Study'. Scan count 4291, logical reads 8582, physical reads 0, read-ahead reads 0.

Table 'LabSample'. Scan count 5647, logical reads 31382, physical reads 308, read-ahead reads 4.

Table 'Form'. Scan count 4291, logical reads 9272, physical reads 2, read-ahead reads 10.

Table 'PrintedLabSampleLabel'. Scan count 4289, logical reads 17097, physical reads 114, read-ahead reads 308.

Table 'ObjectState'. Scan count 6860, logical reads 13760, physical reads 1, read-ahead reads 0.

Table 'Object'. Scan count 6860, logical reads 23559, physical reads 90, read-ahead reads 701.

Table 'PrintedForm'. Scan count 1375, logical reads 4505, physical reads 40, read-ahead reads 16.

Table 'StudySite'. Scan count 1378, logical reads 2756, physical reads 4, read-ahead reads 0.

Table 'Subject'. Scan count 1599, logical reads 3332, physical reads 2, read-ahead reads 0.

Table 'StudyEvent'. Scan count 18, logical reads 52, physical reads 0, read-ahead reads 0.

Table 'StudyEventDef'. Scan count 18, logical reads 54, physical reads 0, read-ahead reads 2.

Table 'FormDefToStudyEventDef'. Scan count 1, logical reads 69, physical reads 0, read-ahead reads 23.

Table 'FormDef'. Scan count 2, logical reads 78, physical reads 1, read-ahead reads 4.

Table 'LabSampleDefToFormDef'. Scan count 1, logical reads 308, physical reads 1, read-ahead reads 306.

Table 'Item'. Scan count 1335, logical reads 36510, physical reads 140, read-ahead reads 1047.

(21234 row(s) affected)

(147 row(s) affected)


One difference between the two is the work table that 2005 creates versus 2000. I can attach the plans but they are huge. I will attach it if you ask.

What I was looking for was suggestions on what I could do short of rewriting code or any suggestions in general.

Thanks

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Hello All,

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It makes me feel I don't use the abilities SSIS has to offer compared to DTS.
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Hi
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No error in the event view

Any idea
TIA
Abel
:angel:

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Jul 23, 2005

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The client production server CPU starts thrashing. Task manager indicates that SQL server is gobbling CPU cycles. Having a look at the replication monitor, it is obvious that indivual synchronisations to the mobile devices are taking significantly longer expected.

Observing an indivual synchronisation attempt, the Upload changes to Publisher rows are very quickly resolved.

The Download changes to Subscriber seems to take up a very long time.

Along the way, the estimated completion does a few interesting things, like going from 100% complete with no estimated time to complete, back to seomthing like 77% with 2 minutes left to complete.

This sort of behaviour occurs when there are only a hundred rows to download.

Synchronisations for minimal amounts of data suddenly taking anywhere from 2 to 15 minutes. Totally unacceptable form the client perspective but seems that 2005 behaves quite different from 2000 and the tricks are yet to reveal themselves.

Note - It is a server hardware issue as there is in excess of 3 GB ram, the database is on a SAN and there are 4 3Ghz CPUS in operation.


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I am currently querying two databases - One in SQL Server and one Oracle, to find records which are in one but not the other (essentially a reconcilliation) this is working fine in MS Access, using 2 passthrough queries to return the results of the 2 databases, then another query to find the data in one but not the other.



I decided to try the linked server approach as I thought this would give me enhanced performance - but strangely enough when I query the oracle database from MS Access the query takes about 22 seconds - whereas when I query the linked server from SQL Server the same query takes about 55 seconds.



The only difernce I can see is the passthrough query in MS Access is connecting using ODBC, an the linked server is connecting using Microsoft OLE DB Provider for Oracle.



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Guys,

We have MSSQL 2000 Server instance installed and working well on Windows 2003 Server machine [IBM X series-366] with 16GB RAM, 3.67GHZ cpu power, and 400GB hard disk space.

We further created an identical server instance on a new machine. More specifically, on Windows 2003 Server machine [Intel (R) Xeon (TM)] with 16GB RAM, 3.67GHZ cpu power, and 400GB hard disk space, we installed MSSQL 2000 Server and copied over all the dbs, applications ...

We were expecting same or similar performance (since processor speed, ram, hd, server and database configurations are all the same, with same indexes on same tables. However, for some reason, there is a noticeable difference in performance.

More specifically, I ran Profiler for 30 minutes on both servers simultaneously [same trace parameters]. The trace file of the new server is 3 times as large as that of the old one (i.e. It looks like more items are being processed). However, the average duration of the executed stored procedures is much longer on the new server than that of the old server.

Moreover, when I run same queries on 2 servers. The query on the new server always takes longer than that on the old server. And for tables where we don't have indexes, it takes much longer.

Following advice here(http://support.microsoft.com/kb/274750/), we configured our new server (just as was our old one configured) to use 15GB of RAM. I further compared the configurations of 2 servers by executing sp_configure (with advance options). The only difference I saw was that "remote proc trans" is set to off on the new server and on on the old server. I don't think it could affect this issue though.

Furthermore, the new server appears to have many more locks, as compared to the old server. Could it be because it is processing more items?

I cannot figure what is causing the queries to be slower on the new server.

Can anyone suggest anything?


Thanks a lot

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Sep 27, 2006

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SELECT trans.Entry_Code, trans.D_C, trans.ADP_Security_# ,
trans.TRID, trans.Batch_Code, trans.Last_Money,
null as Shares, Settle_date as Process_Date,
null as Closing_Price, trans.Dwnld_Date, trans.Acnt,
null as Mktval,
cast(Null as varchar(20)) as Cusip_#,
ACT.dbo.account.account_key AS account_key
FROM (SELECT * FROM ADPDBBOOK.dbo.YTD05B
WHERE (DATEDIFF(mm, Process_Date, GETDATE()) <= 15)
UNION
SELECT * FROM ADPDBBOOK.dbo.YTD06B) trans
INNER JOIN ACT_DATA.dbo.account
ON ACT_DATA.dbo.account.account_key = RIGHT(trans.Acnt, 5)
INNER JOIN tbl_Accounts_TransactionalData
ON trans.Acnt = tbl_Accounts_TransactionalData.Acnt

Thanks, Dave

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If you want to compare the dataabses here are the links:

Access: http://ozeldersverenler.net/beta/www
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Poor Performance Temporarily Cured by Re-booting SQL Server

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Additional information:
Transaction logs are backed up at 13:00 and in the evening (both periods of very low usage).Full backup is run in the evening and at 13:00 (both periods of very low usage), with integrity check performed prior to full backup. Database is optimized after the full backup including shrinking the database leaving 15% of the data space free.

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Dim bufferSize As Integer = 24000
Dim outbyte(bufferSize - 1) As Byte
Dim retval As Long
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Dim sql As String = "SELECT ..."
Dim cmd As New SqlCommand(sql, conn)
conn.open()
Dim dr As SqlDataReader = cmd.ExecuteReader(CommandBehavior.SequentialAccess)
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' Read bytes into outbyte() and retain the number of bytes returned.
retval = dr.GetBytes(DocCol, startIndex, outbyte, 0, bufferSize)
Current.Response.Clear()
Current.Response.Buffer = True
Current.Response.ContentType = "application/octet-stream"
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Current.Response.BinaryWrite(outbyte)
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' Reposition the start index to the end of the last buffer and fill the buffer.
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Feb 22, 2008



Hi All

I decided to change over from Microsoft Access Database file to the New SQLServerCe Compact edition. Although the reading of data from the database is greatly improved, the inserting of the new rows is extremely slow.

I was getting between 60 to 70 rows per sec using OLEDB and an Access Database but now only getting 14 to 27 rows per sec using SQLServerCe.

I have tried the below code changes and nothing seams to increase the speed, any help as I would prefer to use SQLServerCe as the database is much smaller and I€™m use to SQL Commands.

Details:
VB2008 Pro
.NET Frameworks 2.0
SQL Compact Edition V3.5
Encryption = Engine Default
Database Size = 128Mb (But needs to be changes to 999Mbs)

Where Backup_On_Next_Run, OverWriteQuick, CompressAns are Booleans, all other column sizes are nvarchar and size 10 to 30 expect for Full Folder Address size 260

TRY1

Direct Insert Using Data Adapter.

Me.BackupDatabaseTableAdapter1.Insert(Group_Name1, Full_Folder_Address1, File1, File_Size_KB1, Schedule_To_Run1, Backup_Time1, Last_Run1, Result1, Last_Modfied1, Last_Modfied1, Backup_On_Next_Run1, Total_Backup_Times1, Server_File_Number1, Server_Number1, File_Break_Down1, No_Of_Servers1, Full_File_Address1, OverWriteQuick, CompressAns)

14 to 20 rows per second (Was 60 to 70 when using OLEDB Access)


TRY 2

Using Record Sets

Private Sub InsertRecordsIntoSQLServerce(ByVal Group_Name1 As String, ByVal Full_Folder_Address1 As String, ByVal File1 As String, ByVal File_Size_KB1 As String, ByVal Schedule_To_Run1 As String, ByVal Backup_Time1 As String, ByVal Last_Run1 As String, ByVal Result1 As String, ByVal Last_Modfied1 As String, ByVal Latest_Modfied1 As String, ByVal Backup_On_Next_Run1 As Boolean, ByVal Total_Backup_Times1 As String, ByVal Server_File_Number1 As String, ByVal Server_Number1 As String, ByVal File_Break_Down1 As String, ByVal No_Of_Servers1 As String, ByVal Full_File_Address1 As String, ByVal OverWriteQuick As Boolean, ByVal CompressAns As Boolean)

Dim conn As SqlCeConnection = Nothing
Dim CommandText1 As String = "INSERT INTO BackupDatabase (Group_Name, Full_Full_Folder_Adress, File1,File_Size_KB, Schedule_To_Run, Backup_Time, Last_Run, Result, Last_Modfied, Latest_Modfied, Backup_On_Next_Run, Total_Backup_Times, Server_File_Number, Server_Number, File_Break_Down, No_Of_Servers, Full_File_Address, OverWrite, Compressed) VALUES ('" & Group_Name1 & "', '" & Full_Folder_Address1 & "', '" & File1 & "', '" & File_Size_KB1 & "', '" & Schedule_To_Run1 & "', '" & Backup_Time1 & "', '" & Last_Run1 & "', '" & Result1 & "', '" & Last_Modfied1 & "', '" & Latest_Modfied1 & "', '" & CStr(Backup_On_Next_Run1) & "', '" & Total_Backup_Times1 & "', '" & Server_File_Number1 & "', '" & Server_Number1 & "', '" & File_Break_Down1 & "', '" & No_Of_Servers1 & "', '" & Full_File_Address1 & "', '" & CStr(OverWriteQuick) & "', '" & CStr(CompressAns) & "')"
Try
conn = New SqlCeConnection(strConn)
conn.Open()

Dim cmd As SqlCeCommand = conn.CreateCommand()

cmd.CommandText = "SELECT * FROM BackupDatabase"
cmd.ExecuteNonQuery()
Dim rs As SqlCeResultSet = cmd.ExecuteResultSet(ResultSetOptions.Updatable Or ResultSetOptions.Scrollable)

Dim rec As SqlCeUpdatableRecord = rs.CreateRecord()

rec.SetString(1, Group_Name1)
rec.SetString(2, Full_Folder_Address1)
rec.SetString(3, File1)
rec.SetSqlString(4, File_Size_KB1)
rec.SetSqlString(5, Schedule_To_Run1)
rec.SetSqlString(6, Backup_Time1)
rec.SetSqlString(7, Last_Run1)
rec.SetSqlString(8, Result1)
rec.SetSqlString(9, Last_Modfied1)
rec.SetSqlString(10, Latest_Modfied1)
rec.SetSqlBoolean(11, Backup_On_Next_Run1)
rec.SetSqlString(12, Total_Backup_Times1)
rec.SetSqlString(13, Server_File_Number1)
rec.SetSqlString(14, Server_Number1)
rec.SetSqlString(15, File_Break_Down1)
rec.SetSqlString(16, No_Of_Servers1)
rec.SetSqlString(17, Full_File_Address1)
rec.SetSqlBoolean(18, OverWriteQuick)
rec.SetSqlBoolean(19, CompressAns)
rs.Insert(rec)
Catch e As Exception
MessageBox.Show(e.Message)
Finally
conn.Close()
End Try
End Sub

€™20 to 24 rows per sec

TRY 3

Using SQL Commands Direct

Private Sub InsertRecordsIntoSQLServerce(ByVal Group_Name1 As String, ByVal Full_Folder_Address1 As String, ByVal File1 As String, ByVal File_Size_KB1 As String, ByVal Schedule_To_Run1 As String, ByVal Backup_Time1 As String, ByVal Last_Run1 As String, ByVal Result1 As String, ByVal Last_Modfied1 As String, ByVal Latest_Modfied1 As String, ByVal Backup_On_Next_Run1 As Boolean, ByVal Total_Backup_Times1 As String, ByVal Server_File_Number1 As String, ByVal Server_Number1 As String, ByVal File_Break_Down1 As String, ByVal No_Of_Servers1 As String, ByVal Full_File_Address1 As String, ByVal OverWriteQuick As Boolean, ByVal CompressAns As Boolean)

Dim conn As SqlCeConnection = Nothing
Dim CommandText1 As String = "INSERT INTO BackupDatabase (Group_Name, Full_Full_Folder_Adress, File1,File_Size_KB, Schedule_To_Run, Backup_Time, Last_Run, Result, Last_Modfied, Latest_Modfied, Backup_On_Next_Run, Total_Backup_Times, Server_File_Number, Server_Number, File_Break_Down, No_Of_Servers, Full_File_Address, OverWrite, Compressed) VALUES ('" & Group_Name1 & "', '" & Full_Folder_Address1 & "', '" & File1 & "', '" & File_Size_KB1 & "', '" & Schedule_To_Run1 & "', '" & Backup_Time1 & "', '" & Last_Run1 & "', '" & Result1 & "', '" & Last_Modfied1 & "', '" & Latest_Modfied1 & "', '" & CStr(Backup_On_Next_Run1) & "', '" & Total_Backup_Times1 & "', '" & Server_File_Number1 & "', '" & Server_Number1 & "', '" & File_Break_Down1 & "', '" & No_Of_Servers1 & "', '" & Full_File_Address1 & "', '" & CStr(OverWriteQuick) & "', '" & CStr(CompressAns) & "')"

Try
conn = New SqlCeConnection(strConn)
conn.Open()

Dim cmd As SqlCeCommand = conn.CreateCommand()
cmd.CommandText = CommandText1
'cmd.CommandText = "INSERT INTO BackupDatabase (€¦"
cmd.ExecuteNonQuery()

Catch e As Exception
MessageBox.Show(e.Message)
Finally
conn.Close()
End Try
End Sub

€˜ 25 to 30 but mostly holds around 27 rows per sec I

Is this the best you can get or is there a better way. Any help would be greatly appericated

Kind Regards

John Galvin

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Hi..

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I have two tables:
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Attributes :
Company_Id (PK)
Fleet_Id (PK)
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2.USER_PRIVILEGE (The number of rows can reach up to 3 times the number of row in fleet table)
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Company_Id (PK)
Fleet_Id (PK)
User_Id (PK)
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Comment
Category

I want to select Fleet_Id and Fleet_Name from fleet table
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I have two possible select statement :

1.Option 1

SELECT Fleet_Name, Fleet_Id
FROM FLEET
WHERE (Company_Id = 2) AND (Fleet_Id IN
(SELECT fleet_id
FROM user_privilege
WHERE user_id = 11 AND company_id = 2 AND privilege_id = 1))
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2.Option 2

SELECT F.Fleet_Name, F.Fleet_Id
FROM USER_PRIVILEGE U INNER JOIN
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WHERE (F.Company_Id = 2) AND (U.Privilege_Id = 1) AND (U.User_Id = 11)
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Hi:
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Where the '1526858' is a phone number.
My problem is, I want to run the above query for each record in :
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How can I do so? Do I need a loop? a cursor? Can you help please?
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Hi there,
I'm having a big performance problems with sql query. What i have done is changes physical layout (rearanged the columns) in one of the tables in the database. I used bcp to get the data out and then in. There are about quarter million rows in the this table. I have created the same indexes but know the same query takes a long time to execute. I have noticed that the showplan is somehow different than it used to be. This query uses the table i have changed and another one that i haven't touched. I have updated the stats to no help.
Here are the show plans.
this one is slow
STEP 1
The type of query is INSERT
The update mode is direct
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SW_PERSON
Nested iteration
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SW_CASE
Nested iteration
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Worktable 1
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The type of query is SELECT
This step involves sorting
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Worktable 1
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this one used to be fast
STEP 1
The type of query is INSERT
The update mode is direct
Worktable created for ORDER BY
FROM TABLE
SW_CASE
Nested iteration
Table Scan
FROM TABLE
SW_PERSON
Nested iteration
Index : PK_SW_PERSON_1__27
TO TABLE
Worktable 1
STEP 2
The type of query is SELECT
This step involves sorting
FROM TABLE
Worktable 1
Using GETSORTED Table Scan

I think the problem is with the fact that the fist one doesn't use the PK
key which is the one the links both tables. My question is how to force the query to use this index.
PS.
One thing i haven't done is to recreate indexes on the other table. But i don't think that would have made a differnece.
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