We have some databases in a single SQL Server 2000 instance, one of them being a sandbox. My boss needs to be able to restore fresh data over the sandbox using a utility I don't have the source to. Such restores fail if anyone is connected to the sandbox.
Another app I have accessing it uses connection pooling, and also there might be people using other apps to access the sandbox that I can't control.
How can I boot everyone off the sandbox, including the pooled connections, without touching any of the other databases running on the same instance?
(I've seen solutions out there that use Management Studio 2008 (from 2008 Express), but a) I need to be able to do it from the command line or a script somehow so my boss can run it without installing Management Studio, and b) the context menu options they talked about didn't seem to be there anyway.)
I've found it on the web:
ALTER DATABASE db SET SINGLE_USER WITH ROLLBACK IMMEDIATE
create a sp that run this restores, and then restore it to regular.
(ALTER DATABASE foo SET MULTI_USER;)
Related
We have here a application that uses ODAC components inside COM+ dlls to connect to Oracle Server 11g.
Lately we are facing a problem that we cannot find the solution.
For some reason, when the concurrency of the application server at some of our clients is too high, some dlls starts to hang and they have to kill the process to restore the usability of our product. Trying to reproduce the error here at our office, we created a test environment to stress an application server. We start 30-50 programs that make calls to application and after some time the problem appears.
Debugging our DLL after the server hangs, shows that any subsequent call to OCISessionBegin cannot complete. No error is generated. No other symptoms are visible.
The last line that the we try to execute is: Check(OCISessionBegin(...)); on OraClasses.pas
We checked the database no contention, no lock.
We are using ODAC 6 on our clients, but we upgraded it to the last version and the problem persists. We have to use the Oracle Client 10 to connect to the database 11g because the are using the version 6 of ODAC.
Thanks a lot
AFAIK you need to create your environment with both OCI_EVENTS + OCI_THREADED attributes sets, in such a configuration.
For instance, here is how it is initialized in our Open Source direct Oracle access unit:
fEnvironmentInitializationMode := OCI_EVENTS or OCI_THREADED;
...
with OCI do
try
if fEnv=nil then
// will use UTF-8 encoding by default, in a multi-threaded context
// OCI_EVENTS is needed to support Oracle RAC Connection Load Balancing
EnvNlsCreate(fEnv,Props.EnvironmentInitializationMode,
nil,nil,nil,nil,0,nil,OCI_UTF8,OCI_UTF8);
I suspect you have to check how your OCI environment is created in ODAC.
I have an ASP.Net MVC 3 application. I have created a setup for it and installed on my webserver.
When I access the application from a web browser at "http://localhost/myapp", it works.
But when I tried from another machine, like "http://mywebserver/myapp" it's giving an error:
The model item passed into the dictionary is of type 'System.Web.Mvc.HandleErrorInfo', but this dictionary requires a model item of type myapp.Models.ErrorModel'.`
As per:
http://blogs.msdn.com/b/dataaccesstechnologies/archive/2012/08/09/error-quot-the-underlying-provider-failed-on-open-quot-in-entity-framework-application.aspx
It could be a permissions issue on the new server, etc
Solution 1:
In the existing connection string to remove the “user Instance=true” and it works.
Probable cause of the issue could be as below:
The user instance cannot attach the database because the user does not have the required permissions. The user instance executes in the context of the user who opened the connection—not the normal SQL Server service account. The user who opened the user instance connection must have write permissions on the .mdf and .ldf files that are specified in the AttachDbFilename option of the connection string.
Another common issue is when you open a database file successfully when the database is attached to the SQL Server Express instance, but fails when you try to open it from the Visual Studio IDE. This might occur because the SQL Server Express instance is running as "NT AUTHORITY\NETWORK SERVICE," while the IDE is running as windows account. Therefore, the permissions may not work.
A variation of this issue is when the user that opens the user instance connection has read permissions on the database files but does not have write permissions. If you get a message saying that the database is opened as read only, you need to change the permissions on the database file.
The other main issue with user instances occurs because SQL Server opens database files with exclusive access. This is necessary because SQL Server manages the locking of the database data in its memory. Thus, if more than one SQL Server instance has the same file open, there is the potential for data corruption. If two different user instances use the same database file, one instance must close the file before the other instance can open it. There are two common ways to close database files, as follows.
User instance databases have the Auto Close option set so that if there are no connections to a database for 8-10 minutes, the database shuts down and the file is closed. This happens automatically, but it can take a while, especially if connection pooling is enabled for your connections.
Detaching the database from the instance by calling sp_detach_db will close the file. This is the method Visual Studio uses to ensure that the database file is closed when the IDE switches between user instances. For example, you are using the IDE to design a data-enabled Web page. You press F5 to run the application. The IDE detaches the database so that ASP.NET can open the database files. If you leave the database attached to the IDE and try to run the ASP page from your browser, ASP.NET cannot open the database because the file is still in use by the IDE.
For MySQL, the MXJ connector makes it very easy to launch a managed MySQL instance.
I know that Oracle provides Oracle XE for quick setup, but I've only found an RPM distribution that needs to be installed. Is there a neatly packaged jar that I can just drop in the classpath and start up by calling a specific JDBC url, a la HSQLDB or MXJ?
I'm interested in having developers use this locally for running tests, as well as on our continuous integration server.
The short answer is No. Oracle is a big meaty chunk of database. Amongst other things, it generally expects itself to be run by its own special user rather than the client user.
For simplicity, your best bet is a separate DB server with each of your developers having their own username/password (and hence their own independent schema) in the database.
Although Oracle does not provide an embedded database, spinning up a local Docker container running Oracle XE might be an ideal way to accommodate Oracle-specific local integration tests. Since Docker containers are ephemeral in nature by design, the database could also be completely torn down as desired providing clean sandboxing.
The alexeiled/docker-oracle-xe-11g image on DockerHub I found has particularly clear setup and documentation instructions: https://hub.docker.com/r/alexeiled/docker-oracle-xe-11g/
After spinning up the Docker container, be sure to:
First connect to the APEX web console, login, as per the instructions
Then open Oracle SQL Developer and select Reset Password... first. Otherwise the following error may be thrown java.lang.ArithmeticException when attempting to get connection in Oracle 11.2.0.2.0 (64 bit)
As the documentation describes, the docker run command can also be designed to automatically run SQL scripts on the container's startup, which could also be very valuable in the CI/integration testing workflow.
Hope this helps!
I need to automate a selective table / user object backup I currently am doing via PL / SQL Developer.
The way I currently do it is via Tools/Export Tables and Tools/Export User Objects, manually select tables / objects, then set the options, choose destination and export. I do this from a windows laptop and the database is located in a suse linux server, both are in the same LAN. DB is running 24/7 and can not be shutdown. Also currently my oracle programming skills are very basic as I only do maintenance to this solution. I would like to keep doing the backup process in the windows laptop, but I would consider a server side script solution also and then retrieving the .sql files from server.
Thanks in advance
I wouldn't really call it a backup, but look at exp/imp and expdp/impdp (data pump) in the Utilities manual
As Gary implies exp/imp really isn't a backup solution. If this database is important to you or others, figure out how to use RMAN , which is usually configured to run in a mode that doesn't require the database to be shut down. Although it executes on the database host and for non-tape destinations must write its files to a filesystem attached to the host, it can be launched remotely.
RMAN is aimed at restoring/recovering the entire database, so if what you're looking for is only the ability to recover isolated objects it may not be for you.
My team inherited an Oracle-based web application and they are fairly inexperienced with Oracle database servers.
The Oracle 10g server is running on a Windows 2003 Server with plenty of disk space and from time to time, all connectivity is lost, the application stops working, not even SQL Plus is able to connect to the database server.
But when we check the Windows Service manager, it says that the service is up and running. A restart usually fixes the problem, but we need to properly troubleshoot it so we know what's causing it and so we can avoid it to happen anymore.
Where should we start looking for clues? What are the criticial log files we should be investigating?
On the server you should have an environment variable called ORACLE_HOME which indicate the root of the Oracle install. Most likely the Oracle trace/dump folders will be under there. Search for a folder called "bdump" (background dump). That's where the main log file, knows as the alert log, will be, as well as trace files generated by background processes. There will be an adjacent file called "udump" which will contain any trace files generated by user processes.
However, my real advice is that you should either hire someone who knows Oracle or get Oracle Support involved.
The alert log would be the first file to check.
It will probably be in $ORACLE_HOME/admin/bdump and (probably) called alert_DATABASE-SID.log
It contains most of the important actions that the database does, as well as any important errors that occur.
I have to agree with cagcowboy. Check your alert logs for errors. If no errors then maintain a sysdba login into the database and when it hangs, attempt to do a hang analysis. See metalink note 215858.1 on hanganalyze.
Have you tried tnsping? We've occasionally run into problems with the listener that requires an assist from our DBA. tnsping is the diagnostic tool we use to do triage.
I would recommend hiring an experienced Oracle DBA if at all possible.
check the alert log to see how the Db is structured. sometimes badly set parameters make hangs or slow performance. or you can shutdown and start in mount mode, then check the v$parameter values for problems. setting total memory is very important.