Exceute scalar need s an open and availble connection

[pvenkatesh2k4]

hi to all ,
i am new to .Net development.
i have developed a service which doing some operation along with database. i have developed an another application which will insert the data into the database and tells the service to get the inserted data.this application works fine when at a time only one request is sent. but it fails when more than 5 . from service i will connect to database whenever i need and then i will close. the service throws an error "Executescalar requires an open and available connection".how to solve this issue?

thanks in advance

[kenobewan]

What database are you using? Please show us your relevant code. Thanks.

[pvenkatesh2k4]

i am using Sql server 2000:
my database file code is

class DataBase
    {
        OleDbConnection Con;
        OleDbCommand Cmd;
        private void CloseConnection()
        {
            try
            {
                Cmd.Dispose();
                Con.Close();
            }
            catch (Exception excp)
            {
                ErrorLog.WriteError("CloseConnection", excp.Message);
            }
        }
 
        public String GetResult(String Qry)
        {
            String Result = "" ;
            try
            {
                EstablishConnection();
                Cmd.CommandText = Qry;                
                if (Cmd.ExecuteScalar() == null)
                {
                    Result = "Empty";
                }
                else
                {
                    Result = Cmd.ExecuteScalar().ToString();
                    if (Result == "")
                        Result = "Empty";
                }
                CloseConnection();
            }
            catch (Exception excp)
            { 
                ErrorLog.WriteError("Get Result:", excp.Message);
            }
                return Result;
           }
 
        private void EstablishConnection()
        {
            Con = new OleDbConnection();
            Cmd = new OleDbCommand();
            try
            {
                Con.ConnectionString = System.Configuration.ConfigurationSettings.AppSettings["ConnectionString"].ToString();
                Cmd.Connection = Con;
                Con.Open();
            }
            catch (Exception Excp)
            {
                PopupCls.ShowMessage("Error in Database Connection *DataBase");
                ErrorLog.WriteError("Connection Establishment", Excp.Message);
            }
 
        }

Another application will call the service and the service executes the above code


i gets error in the bolded text function execution when the client application calls the service repeatedly;


Thanks in advance

[kenobewan]

Not sure why if (Cmd.ExecuteScalar() == null) else block is necessary or which error is bolded. Try returning boolean values and debugging.

[pvenkatesh2k4]

Not sure why if (Cmd.ExecuteScalar() == null) else block is necessary or which error is bolded. Try returning boolean values and debugging.

thanks for Your reply.Actually i did mistake in objecxt initialization.any way thanks for your replies