Hi,
I would like to use database locking mechanism to control access to an
external resource (like file system).
What I need is
1. an exclusive (write) lock conflicting with any access to the
resource (both for read and write)
2. non-exlusive (read) lock conflicting with writes only
How this could be done?
I'd appreciate any reply.
Vadim
i attached adventure works in sql server 2008 and it showing as read only ,make it read write or remove read only tag from database.
View 11 Replies View RelatedHow to identify whether the files are in read write or read only?
View 1 Replies View RelatedI'm trying to do Sharepoint DR with Log Shipping and every thing configured except one thing which is switch the WSS_Content (Standby /Read-Only) DB to be ready and Write.
I tried from
GUI or ALTER DATABASE [WSS_Content] SET
READ_WRITE WITH NO_WAIT
but I received the below error:
Database WSS_Content is in Warm Standby
I have two database files, one .mdf and one .ndf. The creator of these files has marked them readonly. I want to "attach" these files to a new database, but cannot do so because they are read-only. I get this message:
Server: Msg 3415, Level 16, State 2, Line 1
Database 'TestSprintLD2' is read-only or has read-only files and must be made writable before it can be upgraded.
What command(s) are needed to make these files read_write?
thanks
Can a user of db owner role of a database change the databse option to read only and read-write?If not what permission I need to grant to the user?
View 1 Replies View RelatedHello all,
When I create a new database and replicate to it using BeginMonitoredBackgroundSync :
Code Block
public void BeginMonitoredBackgroundSync(string User)
{
CreateReplicationInstance(User);
repl.BeginSynchronize(
OnSimplifiedSynchronizeComplete,
SqlCeReplication_OnStartTableUpload,
SqlCeReplication_OnStartTableDownload,
SqlCeReplication_OnSynchronization,
repl);
}
private void CreateReplicationInstance(string User)
{
repl = new SqlCeReplication();
string host = repl.HostName;
repl.HostName = User;
string dbFilePath = "";
dbFilePath = System.IO.Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().GetName().CodeBase) +
"\" + repl.HostName + ".sdf";
string myConnectionString = string.Format("Data Source = {0};PWD = {1}", dbFilePath, sqlSettings.Items["SqlPassword"]);
repl.InternetUrl = dynamicsReplicationSettings.ReplicationSettingsItems["InternetUrl"];
repl.PublisherSecurityMode = SecurityType.DBAuthentication;
repl.Publisher = dynamicsReplicationSettings.ReplicationSettingsItems["Publisher"];
repl.PublisherDatabase = dynamicsReplicationSettings.ReplicationSettingsItems["PublisherDatabase"];
repl.PublisherLogin = dynamicsReplicationSettings.ReplicationSettingsItems["PublisherLogin"];
repl.PublisherPassword = dynamicsReplicationSettings.ReplicationSettingsItems["PublisherPassword"];
repl.Publication = dynamicsReplicationSettings.ReplicationSettingsItems["Publication"];
repl.Subscriber = "RemoteSubscription" + repl.HostName;
repl.SubscriberConnectionString = myConnectionString;
repl.ConnectionRetryTimeout = 120;
repl.LoginTimeout = 120;
repl.CompressionLevel = 6;
if (File.Exists(dbFilePath))
{
FileInfo info = new FileInfo(dbFilePath);
if (info.Length <= 20480)
{
File.Delete(dbFilePath);
repl.AddSubscription(System.Data.SqlServerCe.AddOption.CreateDatabase);
}
}
else
{
repl.AddSubscription(System.Data.SqlServerCe.AddOption.CreateDatabase);
}
primeConnection();
}
After the replication finishes, I dispose the replication object like so:
Code Block
void OnAsyncSynchronizeComplete(IAsyncResult asyncResult)
{
try
{
repl.EndSynchronize(asyncResult);
if (repl != null)
{
repl.Dispose();
repl = null;
}
if (ReplicationComplete != null) ReplicationComplete(this, true);
}
catch(Exception ex)
{
if (ReplicationComplete != null) ReplicationComplete(ex, false);
}
}
Then later, if I try to update, insert or delete to the database, the application will hang. I can read from it, but I cannot write. If I close the application down and open it back up without replicating, I will not get any lockups. It also will not hang up after any replications prior to the create replication. I think I am doing something wrong in the initial replication that is holding on to some connection to the DB causing it to lock up. Has anyone seen anything like this before?
hi!
I wonder if anyone can tell me how we can run select queries in an OLE DB data flow task and tell the target SQL 2000 server it should allow reads at all time. Currently when a lock is on the source table our SSIS package will sit and wait untill the lock on the source table is gone.
Thanks.
Marc
Hi,
Yesterday, we have had a sudden load in our SQL Server 2000 which resulted in several locks. There was not too much time to investigate as we had to rush. A team member had reviewed the processes in EM, Manegement, Current Activity. Looking for blocking processes and killed them.
She told me that as soon as the blocking SPID was killed, another one arose and she had to repeat the operation a dozen of time. When done, the server activity was back to normal. She noticed that more than half of the blocking processes showed that they executed the stored Proc "P_SearchProducts".
We don't own the server and the information on what had happened at that time (batches or resource intensive operations, etc.) is not available for now.
The team suggests that we set the Transaction Isolation Level to Read UNCOMMITTED for this SP. I would like to know better about locks before I go ahead.
P_SearchProducts returns 5 recordsets each one could contains from 1 to 200 rows. To achieve the results, it creates about 10 intermediate tables (SELECT ... INTO #TableX) these temp tables are then used progressively to arrive to the final results. Roughly the volume of these temp tables could be double than the final results. The developer who wrote this SP is not a guru in SQL, there is room for improvement. But here are my questions:
Q1. Could the series SELECT ... INTO #TableX in P_SearchProducts prevent or lock another connection from executing the same SP? If yes, under which conditions?
Q2. Let's assume that P_SearchProducts has a slow execution time. Could it prevent another connection from updating the Product table? And thus leading to a deadlock situation? Something like another transaction (by User2) has obtained lock on most of Product tables, except the Product table which were being slowly read by User1 executing P_SearchProducts. But User1 cannot read the other product tables b/c there are locks by User2.
Q3. If the contention issue was provoked by the slow execution time of many request to exec
P_SearchProducts (let's assume there were suddenly 50 users on the web hitting the search product feature at the same time). Could the Read Uncommitted magically resolve the contention issue, providing we accept the consequences of the dirty read.
Sorry for the long post and thank you in advance for any help.
Pls help guys
I need to know whether its possible to read or write in to XML documents from SQLServer directly using stored procedures.
I basically need to created a number of XML documents on a nightly basis.,..........also i need to read a no of XML docs to SQLServer...
Is it wise to use stored procedures for this?
Or are there performance issues.........and do u suggest doing in in .NET
Your comments are appreciated..
Regards
Benny
I have a query that runs for 10 sec on one database( A) and 5 min on another database(B) even though two database have identical scheam, tables, index and statistics..
I ran a profiler and got the below information
CPU READ Write
Database A: 92051 711956 8774
Database B: 91812 7621589 315822
A query runs on database has a significant larger read and write.. I don;t understand why this is happening? even though these two database have the same structure?? it has the same execution plan as well..
How can i solve this issue?
Hi, we're trying to read from a table and write back to the same table and are having a lot of trouble with blocking. What could we do to prevent our application from hanging due to blocking of this type?
View 1 Replies View RelatedHi ..
I want to Write in files or read from files
for example i have My_File.txt . i need a syntax and i want to call this syntax in my Store procedure and this syntax write forexample " Hello Word " in My_File.txt .
and i want another syntax that read from My_File.txt forexample "Word" from My_File.txt . what are those syntaxes do that ??
thanks
Hello,
We currently run sql 2005 server and also sql express in our dev environments. We use sql express as an offline store (smart client). We have a similar/exact schema on the sql 2005 server and also the express.
We use the auto attach feature to connect to the express version of the database. Both the developer machines and the one that is running the sql 2005 server have exactly the same hardware configuration. The only difference may be that the server box is not running the VS.Net environment. The disk space etc is pretty much the same. Actually we run another database server(DB2) on the 2005 server machine.
We have observed that sql express is much slower and queries execute much slower aswell. For example, this may not be a totally scientific way of checking but a long running query on the server took only 2 minutes while on express it took longer than 9 minutes. The schema and data etc are the same.
Is there something we need to look into as far as read write speed/performance goes ?
TIA,
Avinash
Hi,
I am using a Script Component and I have a Read/Write Variable varStatusCase (as assigned in the Custom Properties of my Script Component). I used this inside my script to get a specific value. However, when I ran it I get this error:
The collection of variables locked for read and write access is not available outside of PostExecute.
How do I repair this?
Thanks,
cherriesh
Okay, maybe I'm getting ahead of myself.
Using SQL Server Express, VWD and .net 2.0 I've figured out how to drop a Table Column Constraint or Default Value/Binding and then Create it again using a stored procedure. What I can't figure out is how to retrieve that column's constraint value and write it to, say a label, in an aspx page, simply for reference. Is it possible? In this case the Data Type of the column is money.
I'm using it to perform a calculation to a column with a value that the user inserts into another column. (Column1(user input) minus Column2(with Default Value) = Column3(Difference). I just want to read Column2's Default Value for reference so I know whether to change it or not.
Hi,
I was reading that many of these high traffic websites actually have 2 databases, 1 database is used ONLY for reads, while the other is for writes.
How does one go about creating such a setup? How does the database where writes are allowed replicated the data to the read only database server?
Dear All,
I am looking for a sample code to do read/write operation on SQLCE 3.0 using VC++. For SQLCE 2.0 I have used ATL Consumer template and works well.
Thanks in Advance.
Param
Hello Guys,
in SSIS I want to get a set of data and do some modifications on it before I insert it into the destinatipn. So far so good. Some of the modifications will include comparisions between two columns and if certain field is NULL then I want to get the value from the other one I was comparing to. When using conditional splits, I only get the rows to be redirected so that I can do whatever next. However, I want like use the variables as a storage so that I can put the value of one of the two columns in this variable which will be actually loaded into the destination finally. Any help?
Thanks
I need to create a flat file as word document, may i know how to write text from stored procedure if a file is already exist then the text will append, how to do it ?
Thank you.
I use excel as an interface to write query to retrieve data from a database in network drive. My problem is everyone can open and edit my query. Of course, the univeral database access user name and password will ask but everyone know this.
How can I put password to prevent any query modification?
Thanks
Daniel
Is there a way to get the last read/write time of a table?
I want to have a few tables, but only allow them to exist if they have been used in the last 30 days. I want to set up a "purge" job to clear out any tables that have not been used in 30 days.
Hi All,
I need some help from you experts.
I need to develop something that reads from xml files and writes in to sqlserver, also it should read from SQLServer and writes to xml.
I should be able to give this as a job to exectue daily ,etc.
Can we do this using stored procedures in SQLServer.
Pls paste some sample code, if any or direct me to any url with better info.
Thanks in advance
Hello,
Any help here much appreciated.
I am using sql server 2000 to perform address cleansing. there is a point in my scripting when a table i pass values to becomes read/write.
i suspect this is when i run a cursor through the table.
Is anyone able to confirm for me whether running a cursor changes a table's properties?
Many thanks.
Tim
Ps as the table seems to be read/write it is harder to tell if NULLs are in the table and this is messing with joins I have further down the track.
I want to write a variable say testVar in PostExecute of my script. I also want to read the same variable at the start of my script block.
How to specify this variable in the script transformation editor
ReadOnlyVariables = ????
WriteOnlyVariables = ???
If i just define
WriteOnlyVariables = testVar
will it work . I mean i cannot use testVar in both read & write
Any suggestions...
Thanks
Hello,I'm relatively new to the database world so please forgive me inadvance for my ignorance. I have recently been tasked at my job withfinding a tool that will perform the following tasks: 1) extractschemas from a db, 2) produce a difference report between schemas fromtwo databases, and 3) synchronize two schemas. The purpose is forproduct upgrades during which an existing database schema will need tobe synchronized with a baseline schema.The tool must support the following database vendors (versions givenin parenthesis): Oracle (8i/9i), Sybase (12.x), Informix (9.x), MSS2000, and IBM DB2 (7/8).I have spent the last several days downloading and researching avariety of tools such as Aqua Data Studio, DbVisualizer, DBExplorer,DBDiff, and AdeptSQL. I thought it would be a good idea to post amessage to a few database newsgroups and ask for any recommendationsdatabase developers may have.So if anyone has any recommendations on such a tool or softwarepackage, I would greatly appreciate any information.Thanks!Chad Smith
View 9 Replies View RelatedAny idea to copy a standby/readonly database. We a have a standby/readonly DB from logshipping for hot standby and we would like to make a copy of this standby/readonly DB into a read/write DB in the same server for daily testing. Thanks in advance!
View 6 Replies View RelatedOne of the packages we've created a while ago is now, suddenly, giving us a strange error:
View 3 Replies View RelatedI was wondering if it is possible to read image data from a database in .net compact framework. Since cf does not have image.fromstream(memstream) to work with, I don't know how else to read the image from the database and then place it into a picturebox.
Here is the code I have been trying out:
Dim Img As Image
'
Dim conn As New SqlCeConnection("Data Source = My Documents est2.sdf")
conn.Open()
Dim sql As String = "SELECT * FROM Dater"
Dim cmd As New SqlCeCommand(sql, conn)
Dim reader As SqlCeDataReader = _
cmd.ExecuteReader(System.Data.CommandBehavior.CloseConnection)
While reader.Read()
TextBox1.Text = reader.Item("name")
Dim b(reader.GetBytes(1, 0, Nothing, 0, Integer.MaxValue) - 1) As Byte
reader.GetBytes(1, 0, b, 0, b.Length)
Dim ms As New System.IO.MemoryStream(b)
Dim bmp As New Bitmap(ms) <-Error: Value does not fall within expected range
Img = bmp
End While
PictureBox2.Image = Img
I get an error ,Value does not fall within expected range.
Does this mean the image was not save correctly in the database?
Thanks for any help
Hi,I have a web app, that runs fine, except for one particular section that uses a class called by an event in the code behind. The class resides as a dll in the bin folder. We had no problems during testing, when only one user was running this dll. Problems soon occurred when multiple users tried running it. Here's the error & stack: 06/02/2007 09:25:26 ==> cburns ==> There is already an open DataReader associated with this Command which must be closed first. at System.Data.SqlClient.SqlInternalConnectionTds.ValidateConnectionForExecute(SqlCommand command) at System.Data.SqlClient.SqlConnection.ValidateConnectionForExecute(String method, SqlCommand command) at System.Data.SqlClient.SqlCommand.ValidateCommand(String method, Boolean async) at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method, DbAsyncResult result) at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method) at System.Data.SqlClient.SqlCommand.ExecuteReader(CommandBehavior behavior, String method) at System.Data.SqlClient.SqlCommand.ExecuteReader() at ESP.Validator.Data.DatabaseEvents.DatabaseEventManager.Read(IEventable eventObject, Int16 eventType, DateTime earliestDate, DateTime latestDate) in C:My PathValidatorValidator.NETDataDatabaseEventsDatabaseEventManager.cs:line 92 at ESP.Validator.Data.Translink.CATCard.GetDespatchDate() in C:My PathProjectsValidatorValidator.NETDataTranslinkCATCard.cs:line 94 at ESP.Validator.Data.Translink.ExistingSchemeEntitlement.ReadCards() in C:My PathProjectsValidatorValidator.NETDataTranslinkExistingSchemeEntitlement.cs:line 215 at ESP.Validator.Data.Translink.ExistingSchemeEntitlement.Read() in C:My PathProjectsValidatorValidator.NETDataTranslinkExistingSchemeEntitlement.cs:line 147 at ESP.Validator.Data.Translink.TranslinkApplicant.ReadEntitlements() in C:My PathProjectsValidatorValidator.NETDataTranslinkTranslinkApplicant.cs:line 369 at ESP.Validator.Data.Translink.TranslinkApplicant.Read() in C:My PathProjectsValidatorValidator.NETDataTranslinkTranslinkApplicant.cs:line 353 at ESP.Validator.Data.Translink.PrePrintedLetter.Read() in C:My PathProjectsValidatorValidator.NETDataTranslinkPrePrintedLetter.cs:line 282 at ESP.Validator.ValidationProcessor.Read(ValidationSubject subject) in C:My PathProjectsValidatorValidator.NETValidationProcessor.cs:line 82 at clear_applications_scan_applications.ProcessValidation() It seems the data reader is getting reused. We have ensured after each read the reader is closed. Though all users are using the same connection string. Could it be a connection pool problem, with the connection being overwritten during execution? Should i edit it according to the users logon?I am really at a loss for ideas, and I don't mind admitting I am a bit out of my depth with this one!! Any ideas/suggestions would be greatly appreciated. Thanks
View 1 Replies View RelatedHow would I find the last read/write dates for all the tables within a database.
View 6 Replies View RelatedHow to decrypt or encrypt without making user a db_owner. It is for a web
application and I do not want make the web user a db_owner. Is there a
way to make this work without making the user a db_owner. Currently the
user is a db_datareader and db_datawriter.
I created an asymmetric key
for encryption by password. I am not using a master key because I want
to keep the password seperately on the web server, so a hacker cannot
get access to both if database gets hacked.
These are the steps I took when I logged in to SQL server management studio using windows authentication:
CREATE ASYMMETRIC KEY ccnumber WITH ALGORITHM = RSA_512
ENCRYPTION BY PASSWORD = 'password';
INSERT INTO Payments (CreditCardNumber,enc_CreditCardNumber)
values( '458724124',
EncryptByAsymKey(AsymKey_ID('ccnumber'), '458724124') )
SELECT CONVERT(varchar(50), DecryptByAsymKey( AsymKey_Id('ccnumber'), enc_CreditCardNumber, N'password' ))
AS Creditcardnumber , Creditcardnumber
FROM payments where Creditcardnumber = '458724124'
When
I use the above select statement it works if I make the user a db_owner
but I get null if the user is just db_reader and db_writer.
Is there a way to do encryption without making the user a db_owner?
Hi,
I am back with one more problem..
I have created few reports using SSRS 2005. I am using Oracle database in Data Source to fetch my data. It is working fine and showing me report correctly. But after running the report 8 to 10 times, it starts giving me Memory error. To get rid of that, I need to recycle (stop-start) ReportingService from IIS.
I am exactly getting following error...
Attempted to read or write protected memory. This is often an indication that other memory is corrupt.
I am not getting the actual problem, why is it giving memory error only after running few times? Please let me know if anyone facing same problem or knowing the solution for the problem.
Thanks,
HMaheta