How to determine total number of open/active conne

Question

My PHP/MS Sql Server 2005/win 2003 Application occasionally becomes very unresponsive, the memory/cpu usage does not spike. If i try to open any new connection from sql management studio, then the it just hangs at the open connection dialog box. how to deterime the total number of active connections ms sql server 2005

Answer 1

If your PHP app is holding open many SQL Server connections, then, as you may know, you have a problem with your app's database code. It should be releasing/disposing those connections after use and using connection pooling. Have a look here for a decent article on the topic...

http://www.c-sharpcorner.com/UploadFile/dsdaf/ConnPooling07262006093645AM/ConnPooling.aspx

Answer 2

Use this to get an accurate count for each connection pool (assuming each user/host process uses the same connection string)

SELECT 
DB_NAME(dbid) as DBName, 
COUNT(dbid) as NumberOfConnections,
loginame as LoginName, hostname, hostprocess
FROM
sys.sysprocesses with (nolock)
WHERE 
dbid > 0
GROUP BY 
dbid, loginame, hostname, hostprocess

Answer 3

see sp_who it gives you more details than just seeing the number of connections

in your case i would do something like this

 DECLARE @temp TABLE(spid int , ecid int, status varchar(50),
                     loginname varchar(50),   
                     hostname varchar(50),
blk varchar(50), dbname varchar(50), cmd varchar(50), request_id int) 
INSERT INTO @temp  

EXEC sp_who

SELECT COUNT(*) FROM @temp WHERE dbname = 'DB NAME'

Answer 4

MS SQL knowledge based - How to know open SQL database connection(s) and occupied on which host.

Using below query you will find list database, Host name and total number of open connection count, based on that you will have idea, which host has occupied SQL connection.

SELECT DB_NAME(dbid) as DBName, hostname ,COUNT(dbid) as NumberOfConnections
FROM sys.sysprocesses with (nolock) 
WHERE dbid > 0 
and len(hostname) > 0 
--and DB_NAME(dbid)='master' /* Open this line to filter Database by Name */
Group by DB_NAME(dbid),hostname
order by DBName

Answer 5

As @jwalkerjr mentioned, you should be disposing of connections in code (if connection pooling is enabled, they are just returned to the connection pool). The prescribed way to do this is using the 'using' statement:

// Execute stored proc to read data from repository
using (SqlConnection conn = new SqlConnection(this.connectionString))
{
    using (SqlCommand cmd = conn.CreateCommand())
    {
        cmd.CommandText = "LoadFromRepository";
        cmd.CommandType = CommandType.StoredProcedure;
        cmd.Parameters.AddWithValue("@ID", fileID);

        conn.Open();
        using (SqlDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection))
        {
            if (rdr.Read())
            {
                filename = SaveToFileSystem(rdr, folderfilepath);
            }
        }
    }
}

Answer 6

This shows the number of connections per each DB:

SELECT 
    DB_NAME(dbid) as DBName, 
    COUNT(dbid) as NumberOfConnections,
    loginame as LoginName
FROM
    sys.sysprocesses
WHERE 
    dbid > 0
GROUP BY 
    dbid, loginame

And this gives the total:

SELECT 
    COUNT(dbid) as TotalConnections
FROM
    sys.sysprocesses
WHERE 
    dbid > 0

If you need more detail, run:

sp_who2 'Active'

Note: The SQL Server account used needs the 'sysadmin' role (otherwise it will just show a single row and a count of 1 as the result)