Hi,
Is it possible to place an exclusive row lock when running a SELECT query by using a lock hint (or otherwise).
Basically, when a select statement is run against a table I don't won't any other users to read that row until it has been updated - at some later stage.
Any suggestions on whether this is possible would be welcome.
Thanks,
Karl
Hi All,I have a question about lock hint for you :If the first user currently run a select commandwith share lock and hold it. What kind oflock (lock hint) should be used by the second userin the select command (from the same table) so thatthis command will wait until the first user releasesthe lock ?I have tried using tablock, tablockx, xlock andupdlock hint in the select command for the seconduser, but it is not successful. Below is myunsuccessful test :The first user :Begin Transactionselect fprefix from ut1 where fprefix = '000'The second user :select * from ut1 with (tablockx)Please help meThanks in advanceAnita Hery*** Sent via Developersdex http://www.developersdex.com ***Don't just participate in USENET...get rewarded for it!
View 2 Replies View RelatedCan I use the NO Lock hint when running a SELECT against a view that points to another server? Will the no lock "travel" to the other server through the view?
amk
Anybody know how a SELECT statement can generate an exclusive lock on a table ?
I always thought that SELECT's take out shared locks. Is this something to do with temporary tables generated by ORDER BY's and DISTINCT ?
Rogue SQL below (from Site Server).
SELECT A.i_Dsid, A.i_Aid, A.vc_Val, A.i_Val, A.dt_Val, A.img_Val FROM Object_Attributes A, ( SELECT DISTINCT L.i_Dsid FROM Object_Lookup L , Object_Attributes OA2 (index = IND_vc_Aid) WHERE ((( L.i_ObjectClass = 9999 )) AND ( OA2.vc_Val LIKE ( '999999999.9999999%' ) AND OA2.i_Aid = 99)) AND (L.i_Container_Dsid = 99) AND ( OA2.i_Dsid = L.i_Dsid )) AS B WHERE B.i_Dsid = A.i_Dsid AND A.i_Aid NOT IN( 1, 2, 3, 4, 5 ) ORDER BY A.i_Dsid, A.i_Aid
Can anybody suggest a workaround ? Thanks.
Hello All!
I want to perform 4 or 5 statements as a transaction but I need to make sure that during this complete transaction no one else inserts or deletes records from a table named SomeTable.
So how can I lock MyTable at the beggining of the transaction so that during my transaction no one else can insert or delete anything in table SomeTable?
Thanks!
David
I'm relatively new to SQL and I've come across something that doesn't seem quite right. When an insert becomes part of an transaction I notice an exclusive KEY lock in Enterprise Manager. The table in question was using a Clustered index but I changed that, dropped the table and brought it back in but I still get the lock which keeps all others out of the table. Is this the expected behavior or is there something I am missing? Could the size of the tabe affect things? This is a very small table currently. I'm using MSSQL 7 sp3.
Thanks,
John
Hi ,
I have some issues with deadlock.I am getting deadlock becuase of two
select on same table. The sql server log is like this ,
Select statements should have always shared lock.I am not getting why
its doing exclusive lock and creating deadlock.
5/6/2008 12:38 spid4s Unknown Deadlock encountered €¦. Printing
deadlock information
5/6/2008 12:38 spid4s Unknown Wait-for graph
5/6/2008 12:38 spid4s Unknown Log Viewer could not read information
for this log entry. Cause: Data is Null. This method or property
cannot be called on Null values.. Content:
5/6/2008 12:38 spid4s Unknown Node:1
5/6/2008 12:38 spid4s Unknown KEY: 9:72057594050117632 (8d036f07c58f)
CleanCnt:3 Mode Flags: 0×0
5/6/2008 12:38 spid4s Unknown Grant List 3:
5/6/2008 12:38 spid4s Unknown Owner:0×12E9F160 Mode: S Flg:0×0 Ref:1
Life:00000001 SPID:68 ECID:0 XactLockInfo: 0×353D1C54
5/6/2008 12:38 spid4s Unknown SPID: 68 ECID: 0 Statement Type: SELECT
Line #: 4
5/6/2008 12:38 spid4s Unknown Input Buf: Language Event: (@actDefId
nvarchar(36)@stateList varchar(1)@stateList1 varchar(1)@procRelObjType
smallint@procRelObjIdList varchar(36))
5/6/2008 12:38 spid4s Unknown Requested By:
5/6/2008 12:38 spid4s Unknown ResType:LockOwner Stype:€™OR€™Xdes:
0×2FBB67F0 Mode: X SPID:112 BatchID:0 ECID:0 TaskProxy0×0792E378)
Value:0×38baa20 Cost0/11888)
5/6/2008 12:38 spid4s Unknown Log Viewer could not read information
for this log entry. Cause: Data is Null. This method or property
cannot be called on Null values.. Content:
5/6/2008 12:38 spid4s Unknown Node:2
5/6/2008 12:38 spid4s Unknown KEY: 9:72057594049986560 (6f02e1cd37c3)
CleanCnt:3 Mode:X Flags: 0×0
5/6/2008 12:38 spid4s Unknown Wait List:
5/6/2008 12:38 spid4s Unknown Owner:0×12396EE0 Mode: S Flg:0×2 Ref:1
Life:00000000 SPID:90 ECID:0 XactLockInfo: 0×0AA8178C
5/6/2008 12:38 spid4s Unknown SPID: 90 ECID: 0 Statement Type: SELECT
Line #: 4
5/6/2008 12:38 spid4s Unknown Input Buf: Language Event: (@actDefId
nvarchar(36)@stateList varchar(1)@stateList1 varchar(1)@procRelObjType
smallint@procRelObjIdList varchar(36))
5/6/2008 12:38 spid4s Unknown Requested By:
5/6/2008 12:38 spid4s Unknown ResType:LockOwner Stype:€™OR€™Xdes:
0×353D1C30 Mode: S SPID:68 BatchID:0 ECID:0 TaskProxy0×13B3E378)
Value:0×12e9e780 Cost0/6164)
5/6/2008 12:38 spid4s Unknown Log Viewer could not read information
for this log entry. Cause: Data is Null. This method or property
cannot be called on Null values.. Content:
If you have any idea regarding this please let me know ASAP.
Thanks in advance .
Hello,
We currently use SQL Serv 2000 with an ERP application and VB applications.
Both system work with the same database & tables but the ERP application seems to put exclusive lock on all tables it needs during processes. So our VB applications are not able to read these data and we receive TIMEOUT error.
What can I do ?
thank you
Nico
Is there a place where i can find events that takes place in the sql server? Like adding data to a database or something like that....
Regards
Karen
I simply made my script task (or any other task) fail
In my package error handler i have a Exec SQL task - for Stored Proc
SP statement is set in following expression (works fine in design time):
"EXEC [dbo].[us_sp_Insert_STG_FEED_EVENT_LOG] @FEED_ID= " + (DT_WSTR,10) @[User::FEED_ID] + ", @FEED_EVENT_LOG_TYPE_ID = 3, @STARTED_ON = '"+(DT_WSTR,30)@[System::StartTime] +"', @ENDED_ON = NULL, @message = 'Package failed. ErrorCode: "+(DT_WSTR,10)@[System::ErrorCode]+" ErrorMsg: "+@[System::ErrorDescription]+"', @FILES_PROCESSED = '" + @[User::t_ProcessedFiles] + "', @PKG_EXECUTION_ID = '" + @[System::ExecutionInstanceGUID] + "'"
From progress:
Error: The Script returned a failure result.
Task SCR REIL Data failed
OnError - Task SQL Insert Error Msg
Error: A deadlock was detected while trying to lock variable "System::ErrorCode, System::ErrorDescription, System::ExecutionInstanceGUID, System::StartTime, User::FEED_ID, User::t_ProcessedFiles" for read access. A lock could not be acquired after 16 attempts and timed out.
Error: The expression ""EXEC [dbo].[us_sp_Insert_STG_FEED_EVENT_LOG] @FEED_ID= " + (DT_WSTR,10) @[User::FEED_ID] + ", @FEED_EVENT_LOG_TYPE_ID = 3, @STARTED_ON = '"+(DT_WSTR,30)@[System::StartTime] +"', @ENDED_ON = NULL, @message = 'Package failed. ErrorCode: "+(DT_WSTR,10)@[System::ErrorCode]+" ErrorMsg: "+@[System::ErrorDescription]+"', @FILES_PROCESSED = '" + @[User::t_ProcessedFiles] + "', @PKG_EXECUTION_ID = '" + @[System::ExecutionInstanceGUID] + "'"" on property "SqlStatementSource" cannot be evaluated. Modify the expression to be valid.
Warning: The Execution method succeeded, but the number of errors raised (4) reached the maximum allowed (1); resulting in failure. This occurs when the number of errors reaches the number specified in MaximumErrorCount. Change the MaximumErrorCount or fix the errors.
And how did I get 4 errors? - I only set my script task result to failure
Hi
We are facing an acute situation in our web-application. Technology is ASP.NEt/VB.NET, SQL Server 2000.
Consider a scenario in which User 1 is clicking on a button which calls a SQL stored procedure. This procedure selects Group A of records of Database Page1.
At the same time if User 2 also clicks the same button which calls same SQL stored procedure. This procedure selects Group B of records of Database Page1.
So, its the same Page1 but different sets of records. At this moment, both the calls have shared locked on the Page1 inside the procedure.
Now, in call 1, inside the procedure after selecting Group A of records, the next statement is and update to those records. As soon as update statement executes, SQL Server throws a deadlock exception as follows :
Transaction (Process ID 78) was deadlocked on lock resources with another process and has been chosen as the deadlock victim. Rerun the transaction
We are able to understand why its happening. Its because, Group A and Group B of records are on the same Page1. But both the users have shared lock on the Page1. So, no one gets the exclusive lock in records for update, even though, the records are different.
How can I resolve this issue? How can I get lock on wanted rows instead of entire page?
Please advice. Thanks a bunch.
Pankaj
Query hints exceed maximum command buffer size of 1023 bytes(1029 bytes input).
i tried a long query in BCP because i have to insert a character to one of its fields.
hope somebody had encountered and solved this (sql server 2000). thanks in advance..
Is possible to use like hint with subselect? , i mean i want to find all rows in table A that contains a word in a field(CALLED CONTENT) in table B, concretely in a field called content too, i show you the idea although the syntax is incorrect.
select
' + char (39) + @country + char (39) + ' as PAIS,
A.ID,
A.IDUSUARIO MSISDN,
NULL AS MSISDN_COD,
convert(char(19),A.FECHA_ALVENTO, 121) AS FECHA_MO_LOCAL,
NULL AS FECHA_MO_LOCAL_D,
[code]....
Background:I am currently working on a mission critical web based applicationthat is accessed 24 hours a day by users from just about every timezone. We use MS SQL Server as our database and we have lots ofproblems with time-outs. We used to have lots of problems with locksuntil my management decided that we would use the WITH (NOLOCK) hinton EVERY select statement and WITH (ROWLOCK) on EVERY updatestatement. I have argued since the beginning that the NOLOCK hintshould be the exception and not the rule. Meanwhile we continue tohave problems related to time-outs.Problem:I'm the one that they call when there are time-out errors.I am a programmer first and a DBA when I have to be. I'd really liketo hear from some of you who are the opposite. I realize that thereare many factors that contribute to slow response from a databaseserver (indexes, RAM, disk speed, etc.), but what I really need tohear from an expert is whether or not using NOLOCK on **EVERY** queryin a 30GB database that has 344 tables is a bad idea.Thanks in advance,Stephen McMahonJoin Bytes!
View 2 Replies View RelatedHi,
I have set of 2 DTS packages, one of which calls the other by forming a command-line (dtexec) using a Execute Process task.
From the parent package-> Execute Process Task->
dtsexec /F etc... /<pkg variable> = "servername"
Each of the parent and the called package have a variable: "User::DWServerSQLInstance" which is mapped to the SQL server connection manager server name property using an expression. The outer package has the above variable and so does the inner called package (which gets assigned through the command line from the outerpackage call to inner)
I "sometimes" get the following error:
OnError,I4,TESTDOMAdministrator,ACDWAggregation,{A1F8E43F-15F1-4685-8C18-6866AB31E62B},{77B2F3C7-6756-46EB-8C01-D880598FB4B3},5/22/2006 5:10:28 PM,5/22/2006 5:10:28 PM,-1073659822,0x,The variable "User::DWServerSQLInstance" is already on the read list. A variable may only be added once to either the read lock list or the write lock list.
Help would be appreciated!
I have seen other posts on this but, not able to relate the solution to my scenario.
Hi all
If i have a view:
CREATE VIEW vw_Users
AS
SELECT * FROM Users WITH(NOLOCK)
Is it suggested to use nolock in views?
And if i needed to use this view in stored procs is it then suggested to apply the nolock hint?
CREATE PROC [dbo] .[usp_GetCompanyUsers]
AS
SELECT * FROM Companies WITH(NOLOCK) JOIN
vw_Users WITH(NOLOCK) --<< ---is this suggested?
Is possible to use like hint with subselect? , i mean i want to find all rows in table A that contains a word in a field(CALLED CONTENT) in table B, concretely in a field called content too, i show you the idea although the syntax is incorrect.
select
' + char (39) + @country + char (39) + ' as PAIS,
A.ID,
A.IDUSUARIO MSISDN,
NULL AS MSISDN_COD,
convert(char(19),A.FECHA_ALVENTO, 121) AS FECHA_MO_LOCAL,
NULL AS FECHA_MO_LOCAL_D,
[code]...
Can someone give me the right syntax for using an index hint in a delete statement as below?
DELETE table1 WITH (INDEX('indexname_IX'))
WHERE datecolumn < @datevariable
I get this error message:
Incorrect syntax near the keyword 'index'.
I'm using Query Analyzer in SQL 2000 Enterprise.
Thanks,
Gerald
Hi there,
I need to get back the actual characters (without trailing blanks) contained in a char(43) field.
So i tried:
- substring(fieldname,1,len(fieldname)) which yields a 43 char column
- using a variable that contains the actual length in
substring(fieldname,1,@nchar)) the same.
- tricking by concatenating the resulting string with a dummy like "" didn't
work either.
So apparently I am at a dead end.
Anybody a clue, hint or solution????
Thanks to all contributors
We are discovering that adding Force Order to a query is substantially increasing performance. Any issues around using this ?
Craig
According to what I see in BOL, the following should work:
delete
from dbo.tbl1 WITH (INDEX(idx_un01))
where tbl1_no = 1
Yet when I syntax check this I get:
Msg 1069, Level 15, State 1, Line 2
Index hints are only allowed in a FROM clause.
(Please ignore the fact that index hints are unnecessary / a bad idea / etc.)
Hi,
I want to implement the following pattern (pseudo-code follows):
[for index in x different databases, where x is rather big]
create database MyDatabase_#{index}_Temp
launch a dedicated ssis package on this database
if I detect no error, proudly rename MyDatabase_#{index}_Temp to MyDatabase_#{index}_Last_Known_Good (drop the last_known_good first if it exist)
Later on, a consolidation process collect the data in Last_Known_Good versions of the databases.
My question: what is the simpliest way to achieve the rename operation (step 3) ?
I have tried an "alter database #{old_database_name} modify name = #{new_database_name}", but it works only once: once renamed, the database keeps the old mdf and ldf filenames, and the next create database will choke on this.
I have also tried to rename the logical filenames with ALTER DATABASE XXX MODIFY FILE (NAME = YYY, NEWNAME = ZZZ) but it doesn't work either.
I'd like to avoid specifying absolute mdf and ldf filenames myself, is it possible ?
best,
Thibaut
An interesting discussion yesterday. One of the programmers asked about the use of the NOLOCK optimizer hint with an iterator table aka table of numbers. His comment was that this optimizer hint was not efficient. Rather than give a knee-jerk response I thought it would be better to ask. The main circumstance is that the iterator table is completely static with a fill factor of 100%. My purpose is to eliminate lock contention if I can.
Are there reasons to not use the NOLOCK hint in this case to potentially improve performance?
Dave
Hi All,
I have seen a few other people have this error.
Package works fine when run from BIDS, DTExec, dtexecui. When I schedule it, It get these random errors. (See below)
The main culprit is a variable called "RecordsetFileDIR" which is set using an expression. (@[User::_ROOT] + "RecordSets\")
A number of other variables use this as part of their expression and as they all fail, pretty much everything dies.
I have installed SP1 (Not Beta) on server. Package uses config files to set the value of _ROOT.
The error does not always seem to be with this particular variable though. Always a variable that uses an expression but errors are random. Also, It will run 3 out of 10 times without a problem. I am the only person on the server at the time.
Any ideas?
Cheers,
Crispin
Error log:
OnError,,,POSBasketImport,,,10/05/2006 12:03:34,10/05/2006 12:03:34,-1073659822,0x,The variable "User::RecordsetFileDIR" is already on the read list. A variable may only be added once to either the read lock list or the write lock list.
OnError,,,POSBasketImport,,,10/05/2006 12:03:34,10/05/2006 12:03:34,-1073639420,0x,The expression for variable "rsHeaderFile" failed evaluation. There was an error in the expression.
OnError,,,DF_Header_Header,,,10/05/2006 12:03:34,10/05/2006 12:03:34,-1071636247,0x,Accessing variable "User::rsHeaderFile" failed with error code 0xC00470EA.
OnError,,,Move All Data,,,10/05/2006 12:03:34,10/05/2006 12:03:34,-1071636247,0x,Accessing variable "User::rsHeaderFile" failed with error code 0xC00470EA.
OnError,,,Load Open Batches and Process Files,,,10/05/2006 12:03:34,10/05/2006 12:03:34,-1071636247,0x,Accessing variable "User::rsHeaderFile" failed with error code 0xC00470EA.
OnError,,,POSBasketImport,,,10/05/2006 12:03:34,10/05/2006 12:03:34,-1071636247,0x,Accessing variable "User::rsHeaderFile" failed with error code 0xC00470EA.
OnError,,,DF_Header_Header,,,10/05/2006 12:03:34,10/05/2006 12:03:34,-1071636390,0x,The file name is not properly specified. Supply the path and name to the raw file either directly in the FileName property or by specifying a variable in the FileNameVariable property.
OnError,,,Move All Data,,,10/05/2006 12:03:34,10/05/2006 12:03:34,-1071636390,0x,The file name is not properly specified. Supply the path and name to the raw file either directly in the FileName property or by specifying a variable in the FileNameVariable property.
OnError,,,Load Open Batches and Process Files,,,10/05/2006 12:03:34,10/05/2006 12:03:34,-1071636390,0x,The file name is not properly specified. Supply the path and name to the raw file either directly in the FileName property or by specifying a variable in the FileNameVariable property.
OnError,,,POSBasketImport,,,10/05/2006 12:03:34,10/05/2006 12:03:34,-1071636390,0x,The file name is not properly specified. Supply the path and name to the raw file either directly in the FileName property or by specifying a variable in the FileNameVariable property.
OnError,,,DF_Header_Header,,,10/05/2006 12:03:34,10/05/2006 12:03:34,-1073450901,0x,"component "rsHeader" (365)" failed validation and returned validation status "VS_ISBROKEN".
OnError,,,Move All Data,,,10/05/2006 12:03:34,10/05/2006 12:03:34,-1073450901,0x,"component "rsHeader" (365)" failed validation and returned validation status "VS_ISBROKEN".
OnError,,,Load Open Batches and Process Files,,,10/05/2006 12:03:34,10/05/2006 12:03:34,-1073450901,0x,"component "rsHeader" (365)" failed validation and returned validation status "VS_ISBROKEN".
OnError,,,POSBasketImport,,,10/05/2006 12:03:34,10/05/2006 12:03:34,-1073450901,0x,"component "rsHeader" (365)" failed validation and returned validation status "VS_ISBROKEN".
Hi,
When I open an application, it prompts me for a message that SQL is locked in exclusive mode by other application.
How to solve this?
thanks in advance
christine
Is there a way to do a logical exclusive OR (XOR) in sql server?
I'm trying to do this in where clause, something like:
WHERE
(not exists (select 1 from table a where a.date > '01/30/03') XOR
exists (select 1 from table a where a.date < '01/30/03'))
Thanks!
Hi,
How do you lock a table in exclusie mode before running a query?
thanks,
A problem about many to many relationships from an SQL beginner. Here's a contrived abstract example, as I'd prefer not to give away specifics.
Imagine I have two tables: users, food
The relationship (to like) is many-to-many so I've got a link table, which might look like the below:
andrew, apples
bob, banana
bob, apples
chris, carrots
chris, apples
chris, banana
I want to select users who like bananas and apples exclusively.
The answer should be 'bob' ONLY. select * from users inner join food on <IDs> where food in ('bananas','apples') isn't suitable , because it'll also return 'chris' who should be disqualified (because he also likes carrots).
Apart from potentially being bad DB design (although this is an abstract example; I do have ID numbers), can anyone suggest how to get this in a scalable way?
My God! What happens if I miss a step, or put it in a different order??? I know I can specify ORDER BY StepID, but what about a missing step? I do have "missing ranges" script, but posting questions filtered through the script process may become a full-time job in itself...What to do, what to do...
View 14 Replies View RelatedHi All,I want to lock 2 tables on 2 servers using TABLOCKXhint. These tables function as semaphores in myapplication. It means when the tables are lockedthen other users will not be able to access themand automatically they can not continue their works.I have tried using the following code, but itdoes not work. I always got the error :"Cannot specify an index or locking hint fora remote data source" on the select command.begin transelect * from server1.accounting.dbo.semtabwith (tablockx) where fprefix = '000'select * from server2.accounting.dbo.semtabwith (tablockx) where fprefix = '000'--commit tranThe error will disappear if I remove the servername, like this :select * from accounting.dbo.semtabwith (tablockx) where fprefix = '000'But, it does not meet my requirement.It only locks one table on one server(default).Please help meThanks in advanceJohn S.*** Sent via Devdex http://www.devdex.com ***Don't just participate in USENET...get rewarded for it!
View 9 Replies View Related
Hello!
I would like when I compare query plans to be able to compare
2 queries where the 1. is the "normal" version and the 2. the version where I forced compiler
not to use a specific index (i don't want to force at table scan, so hint index(0) can't be used).
The only way I see how I could achieve something similar is to to drop the index and compare response time
before and after. But building index could be time consuming...
Is it possible?
select col42 from tbl;
select col42 from tbl with...
pressing CTRL+L
Greetings
Bjørn
I've got a dilemma which I hope someone has a solution to.
Let's say we're building a data mining model to predict aircraft reliability. In the training table we've got a column (among many others) with a unique aircraft ID, and then a column for the type (737,747) and then a column for the series (100,200,300). I.E. A 737-800 series would be "737" and "800".
There is in essence a parent-child relationship between these 2 columns. 737's should share a common set of reliability factors, and then those factors might be further defined by the series number (for instance, the 737 might have very reliable radar except for the 500 series). The series is analogous to what model year a car is. What I want to make sure doesn't happen is for the system to correlate a 747-400 and a 737-400 because they are the same series. They are totally independent if the model number is different.
My only idea was to merge the columns and have a single value "737-100". But it would seem then that the model won't have any idea that a "737-100" and "737-200" should have a lot more in common than a "737-100" because the values will be completely different.
I was hoping to find some sort of parent-child hint in the column properties but found none.
What solutions have other people tried? It sure seems that there should be an elegant solution for something like, but I'm missing it.
Geof
Hello
we have two SqlServer 2005 in cluster. The machines act very slow (although the CPU load is low) as soon as we achieve one of these operations:
- drop / create database
- restore database
We achieve those operations through the SqlServer Browser or via sqlcmd.
Everything else is running smoothly.
Is there any known reason on why it can be so slow ?
best regards
Thibaut
(hope this is not too OT, but could not find any cluster-specific forum).