Based on these system scalar Functions:
##CONNECTIONS:This function returns the number of attempted connections - both successful and unsuccessful - since SQL Server was last started.
##MAX_CONNECTIONS: Returns the maximum number of simultaneous user connections allowed on an instance of SQL Server. The number returned is not necessarily the number currently configured, returns always 32767.
My Question is this: We know millions of users can connect to sql server at the same time why ##MAX_CONNECTIONS says that only 32767 users can connect to sql server at the same time.
Microsoft covered this topic describes how to set the user connections server configuration option in SQL Server 2017 by using SQL Server Management Studio or Transact-SQL.
The user connections option specifies the maximum number of simultaneous user connections that are allowed on an instance of SQL Server.
The actual number of user connections allowed also depends on the version of SQL Server that you are using, and also the limits of your application or applications and hardware. SQL Server allows a maximum of 32,767 user connections. Because user connections is a dynamic (self-configuring) option, SQL Server adjusts the maximum number of user connections automatically as needed, up to the maximum value allowable.
For example, if only 10 users are logged in, 10 user
connection objects are allocated. In most cases, you do not have to
change the value for this option. The default is 0, which means that
the maximum (32,767) user connections are allowed.
more description here
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We have a Server A and a Server B.
In Server A we have our ERPs made in Access and VBA.
In Server B we have an instance of SQL Server that needs to stay in that server.
Some Access databases need to link to some tables from that SQL Server instance and I don't want the password to be stored in the MSysObjects table, so I cannot manually link the tables checking the save the connection option.
I saved the connection string in a table with password obfuscation. With that connection string I re-link the tables on startup.
The instance is accessed through it's IP, not the name of the instance. If I use the name of the instance it doesn't work.
It works for me but not for other users except one.
The SQL Server instance has been properly configured to allow remote connections, the ports have been opened and rules added to firewall. If it wasn't properly configured it wouldn't work for me and the other user, so I'm pretty confident in that. The same with the connection string and the methods to stablish the connection in Access.
What I've tried:
Installing the SQL Native Client 11.0.
Installing a full SQL Server Express.
Configured the SQL Browser service to star automatically instead of being disabled.
Step 1 did not work for any user. Step 2 did work for one user but not for the rest. Step 3 did not had any effect. For me I had it installed in my machine since forever, so it doesn't apply.
If I try to do the same with a SQL Server instance in our LAN it works for every user, but not when the instance is in a remote server.
Note I have limited knowledge. Maybe I say something that does not make sense.
Ok, a few things:
Installing the SQL Native Client 11.0.
Ok, then you have to re-link the tables - choose the new driver. A refresh of the linked tables is NOT sufficent. And this ALSO means that each work station ALSO now must have native 11 instlled. And if you say decide to link using native 17 (a much newer odbc driver), then AGAIN YOU must install this native driver on each work station. While you can install multiple sql drivers on each workstation, the driver you used to link the tables MUST ALSO be installed and exist on each work station.
Installing a full SQL Server Express.
Why? What would installing a copy of sql server have to do with OTHER sql servers on other machines that you are attempting to connect to? You think installing sql server on a machine effects the sql server running say on amazon.com? So, this move makes no sense at all.
You are attempting to connect to some instance of sql server running on some other computer. Makes no sense nor will it help to install some copy of sql server that you not using, not connecting to, and that has zero to do with this issue.
Configured the SQL Browser service to star automatically instead of being disabled.
Where? The browser service is set to run and startup on the server and SAME machine where sql server is installed and running. So, yes, without question, those two sql servers A, and B most certainly MUST have the sql browser service running. That service is what allows the client computers to connect to that running instance of sql server. In the past, older (previous) versions of sql server would allow a default connection, but now in near all cases, you MUST ensure that the sql browser service is running on that computer that also has the database you are attempting to connect to.
it's worth to note that the instance is accessed through it's IP, not the name of the instance.
No, you likly have this incorrect. There are two part.
The server name - and then the "instance" of sql server running.
While you can swap out (not use) the server name, you STILL WILL NEED to specify the sql server instance.
So, you can use this format:
myservername\SQLEXPRESS
Or, you can replace the server with a IP address, but you STILL NEED the sql server instance. (by default, it is SQLEXPRESS - but you have to check what the instance of sql server database is).
192.168.1.30\SQLEXPRESS
So while you can use IP or server name - it is often more reliable to use the IP address, but that does NOT get you off the hook from having to specify the sql instance you connect to. Again, previous editions of sql server often allowed a "default" instance, and you did not in general have to specify the "instance", but now you do. And to be double clear, when using such a instance, that sql server needs to be running the sql browser service. (in fact, the browser service is what translates the incoming request to the given and correct instance of sql server).
I DON'T want the password to be stored in the MSysObjects table,
You don't have to, and in fact should NOT include the uid/password in your connection string. And in fact ZERO reason exists to do so.
What you do is execute a one time logon, and THEN link the tables without UID/password. This is not only a great idea, but it also means that your uid/password is not included in the connection strings, but also means users can't get at, or even by accident see/get the uid/password.
It also means that say someone where to launch a copy of access, and import the linked tables from this applcation. When they attempt to use the linked tables, they will NOT work.
So, then how do linked tables work without a password? (and this ALSO by the way saves you from having to re-link tables on startup!!!).
The way this works, is you in code execute a one time logon to the server on startup. That means you can either:
Prompt the user for their sql UID/password.
or
Have in code, the uid/password. (or perhaps in a text file y ou read on startup. You can thus hide, or encrypt or whatever for that uid/passwords.
Then in your startup code, you execute a one time logon. Once you done this, then all linked tables will now work - and work without having uid/password.
since you have two servers then you need to execute two logons, one for server A, and one for server B. But, once again, as long as the linked tables exist, then they will work.
Now, there are "longer" articles on how to use this logon idea, and then not have to include, or re-link your tables for the SQL uid/password.
The basic code to execute a logon is like this:
Function TestLogin(strCon As String) As Boolean
On Error GoTo TestError
Dim dbs As DAO.Database
Dim qdf As DAO.QueryDef
Set dbs = CurrentDb()
Set qdf = dbs.CreateQueryDef("")
qdf.connect = strCon
qdf.ReturnsRecords = False
'Any VALID SQL statement that runs on server will work below.
' this does assume user has enough rights to query built in
' system tables
qdf.sql = "SELECT 1 "
qdf.Execute
TestLogin = True
Exit Function
TestError:
TestLogin = False
Exit Function
End Function
Keep in mind, that ONCE you acheived a legal logon, then EVEN addtional logon attempts will return true.
Not usually a big deal, but this means you supply a valid connection to above, and if it logs on and works - then now all your linked tables (without uid/password) will work.
I note the above issue that ONCE you done the logon, then all 2nd or more times running the above will work (even if bad or incorrect!!! - DO NOT forget this tip!!!). (this can confuse the daylights out of a developer, since they execute logon, (or open a table). Then they test above routine with a BAD uid/passwords, and it works!!!
So, you have to EXIT access to clear out the password cache - no other way.
So, keep the above tips in mind.
Our ColdFusion 2016 Enterprise server (Windows Server 2012 R2) is not maintaining connections to an Azure Data Warehouse. The first Azure query on a page takes a second or more to run. Subsequent Azure queries on the same page take a fraction of a second, e.g.:
test1 (Datasource=azureDev, **Time=3485ms**, Records=1) in D:\DW\dwtest\CF2016\bob\azureAdhoc.cfm # 12:10:12.012
select count(*) cnt from dimpatient where name like 'smith%' and birthdate >'2014-02-01'
test2 (Datasource=AzureDev, **Time=125ms**, Records=3) in D:\DW\dwtest\CF2016\bob\azureAdhoc.cfm # 12:10:12.012
select * from dbo.dimPatientMergeStatus
test3 (Datasource=azureDev, **Time=281ms**, Records=1) in D:\DW\dwtest\CF2016\bob\azureAdhoc.cfm # 12:10:13.013
select count(*) cnt from dimpatient where name like 'jones%' and birthdate >'2004-02-01'
It seems apparent that CF is taking extra time to actually make the connection while running the first query on the page. We've tried with various queries and re-arranging their order and always end up with the same result.
We are connecting to Azure using the latest MS jdbc driver (mssql-jdbc-6.2.2.jre8.jar) and 'Maintain Connections' is checked. We first attempted to connect using the built in Microsoft SQL Server driver but kept getting this error:
Connection verification failed for data source: AzureDev2
java.sql.SQLException: [Macromedia][SQLServer JDBC Driver]Error
fetching requested database meta-data info.
We do not see this issue when we run the queries in SSMS.
Any idea what might be wrong?
How does ColdFusion Server manage database connections when there are client variables?
With ColdFusion Server version 4.5.1 SP1 and higher, when you store
your client variables in a database, your code connects to the
database only when a variable is set. This prevents unnecessary
database connections, for instance, in a case where you are using
client management, but no client variables are present in a particular
request.
https://helpx.adobe.com/coldfusion/kb/database-connections-handled-coldfusion.html
I have a an application where you can log on to either MS-SQL 2012 and MS-SQL 2008.
Fields that can be defined are:
Server IP
Database Name
User Id and Password
Schema Prefix
Previously I had no issues with this.
Now I am puzzled.
I am told MS-SQL 2012 and MS-SQL 2008 are on same box with same IP.
I googled this arrangement and it is quite OK to do that.
I have no mental picture of how connecting to one or both of these servers might be carried out.
Are these two installs folded into one? Do they listen on the same port 1433?
Should I be able to access using just the 4 fields I can specify?
Server IP,Database Name, User Id and Password and Schema Prefix.
Help if you can, please ;-)
Tony
No, that is not enough information to reach separate SQL Server instances on the same server.
When installing multiple instances of SQL Server, only one instance can be a default instaince, the other instances have to be named instances. Thus, you also need the instance name to reach one of the databases.
However, if the IP address is not strictly only an IP address but a string, you can include the instance name. Example:
123.14.314.73\sql2012
(Note: IP addreses with components above 255 are reserved for examples and movies. ;) )
I have a problem in WSO2 DSS, the database connection timeout is occurring after a few hours, then I have to stopping and starting the DSS to work.
The DSS version is 2.5.1
the database server is sql server
can help me ? Thank
Have you properly configured your datasource that's used in the dataservice descriptor file to enable "validationQuery" parameter to "SELECT 1" (validation query can vary depending on the RDBMS type used but for SQL server you can use the aforementioned query) and "testOnBorrow" parameter to "true"?
To give you a bit of context on the issue, any RDBMS type by default has a connection timeout value defined. For example, MySQL has a default timeout of 8 hours by default. When connection pooling is used in an application, the connections are kept in the pool once they are created without physically closing to reuse them. However, after the aforementioned period of time, the connections become stale and you have to validate the connections before using them. This is done by specifying a validation query which will be executed whenever a pooled connection is reused. and the "testOnBorrow" parameter comes handy as, when specified, it will validate the pooled connections when they are borrowed from the conneciton pool.
Cheers,
Prabath
// MS SQL Server 2008.
My application has several different connections to sql server database (C#, ADO .NET). Each connection uses the same user name and password. Some connections may execute simultaneously.
Is there any problem with that ? Should I add some settings to support that functionality ?
Is there any settings in connection string that allow/restrict simultaneous connections ? Is there any settings in SQL Server that allow/restrict that functionality ?
No this is normal. Using the exact same connection string also helps with pooling the connections (In the background your connections to the DB are kept open and reused rather than completely closing and opening them).
No. Absolutely not. I is quite normal (in many scenarios you use an app server that uses a specific logon on the sql server - not one per user) and may have thousand of connections open at the same time.
There is no restrictun, no setting. it is considered normal use.
MS SQL Server is designed to handle simultaneous connections, no matter which user they come from. I can't see how you'd have a problem, unless the connections are working on the same data.