Instance , session in SQL Express

Sorry but i need to know even it's very easy for all :

what is a session?

what is an instance?

if i use SQLExpress how meny people will be allowed to connect in same time to dataBase.?

is there another free DBManager, but is it better than SQLExpress?

thanks.

hi

I do not know if, for "session", you mean the process id assigned to the logged user, formerly SPID..

an instance, is an installation of SQL Server, with all it's binaries and databases.. you can install several instances per computer, even at different service pack levels, in different editions and versions..

poorly speaking, SQLExpress allow multiple connections by different users.. there's no actual limit in that number, only the 32767 limit valid for all editions of SQL Server.. but, SQLExpress is allowed to use up to 1 gb of RAM and 1 single CPU (even if in multicore scenario, all cores are usable)... the memory limit is the relevant one we have to deal with.. within that limit all SQLExpress resources are allocated, even user's connection structures, as long as caches for query plans, data caches and the like.. but when to much users are connected performing very different tasks (in term of queries) the 1gb limitation will bi hit, as caches should/would be emptied and flushed to allow all differents operations.. as releasing and refreshing caches costs a lot, in term of IO operations as well as in term of CPU and the like, SQLExpress could become "to limited" in heavy multiuser scenario, with high latency and the like..

DbaMgr and DbaMgr2k (thank you for your interest in) has been written for SQL Server (and MSDE) 7.0 and 2000, as no official tool has been released by Microsoft to manage MSDE instances.. but now Microsoft has release SQL Server Management Studio Express, the official one you can and should use

regards

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thanks for reply, i found this in this forum :

"All Visual Studio Express products use a special type of SQL Connection called a User Instance by default. A User Instance is a special instance of SQL Express (More Info: http://msdn.microsoft.com/sql/express/default.aspx?pull=/library/en-us/dnsse/html/sqlexpuserinst.asp) that offers some usefull developer productivity.

By contrast, Management Studio Express (SSMSE) uses the default instance of SQL Express, typically (local)\SQLEXPRESS.

Since a database can't be connected to two instances of SQL at one time, you are seeing an error. User Instances support the ability to Auto-disconnect a database, so once you shut down your copy of VS, the database is disconnected."

so sincerely i don't rely understand...please help.

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hi,

User Instances "are" a case use of SQLExpress, as you wrote, used by default by VS Express designers... more, VS Express designers, can only connect to User Instances, but you, in your application code, can connect to "traditional" instances as well..

the linked article provides detailed info about this use scenario..

regards

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Thank you andrea that helped me