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close connection

Posted By:      Posted Date: October 04, 2010    Points: 0   Category :ASP.Net


I am using a adapted version of


Don't we need something like a closing-routine / close connection command after getting data from the database?

If yes: What is the correct closing command?


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When establishing a connection with a SQL databse using a try catch Does the try catch close the dat

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SQL server connection - keep it opened all the time, or open/close on demand ?



I have a VB6 app that gets data from several devices and has to store it in a SQL server 2005 database.
It may have to store small amounts of data (a few KB at most) somewhere between 5 and 500 times per day.
My app only sends data to DB, doesn't read anything.

My question is what's better in this case:

a) the app opens a connection to DB at startup and closes it at exit, or
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Open vs Close Connection


Hi Guys,

I have a question related to  leave a SQL connection open or close it.

Here is the scenario...

I have an Intranet page that monitors a Robot, that webpage needs to be up 24hours/7days a week.

Robot sends information to a SQL database every couple of seconds or minutes depending on the work it performs.

My page has an AJAX Timer that triggers every 5 sec, in that page I have to query the database (simple SELECT - no more then 15 lines) and show my info in a gridview.

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Connection Close, Data.CommandBehavior.CloseConnection


Please can you check the following code and tell me if I need to close the connection?

On the following Click Event, first loading SqlDataReader into DataTable and than calling ExportCSV Procedure (passing loaded Datatable)


Protected Sub ExportCSV(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnExportOrders.Click
Dim dt As DataTable = New DataTable()

dt.Load(CoreAdmin_.ExportOrders)  '/// Calling SqlDataReader Code as below "ExportOrders()"

CoreAdmin_.ExportCSV(dt, "ExportOrders_" & FormatDateTime(Now(), DateFormat.ShortDate) & "") '/// Calling Public Shared Sub ExportCSV

dt.Dispose()  '/// <<<<<<  Do I need to Dispose it here ???????
end Sub


Public Shared Function ExportOrders() As SqlDataReader

Dim cn As New SqlConnection
cn = New SqlConnection(ConfigurationManager.ConnectionStrings("SiteConn").ConnectionString)
Dim cmd As New SqlCommand("sp_ExOrders", cn)
cmd.CommandType = Data.CommandType.StoredProcedure

Return cmd.ExecuteReader(Data.CommandBehavior.CloseConnection)
Catch e As Exception
Throw e

Close DB Connection upon application termination?


The reason this question came up, is because if I run my website application with a SQL Server data store, and I terminate the browser (terminating the session), I try to open up SSMS to edit the DB.  But I can't access the database because I believe there is still an open connection, even after application termination.

Is it recommended to close the database connection upon session/application closing?  Or am I way off on what I'm thinking could be the problem?

Thanks in advance. :)

need to close the connection.

  public static int UpdateLastLogin(string userName, string sessionID)

    if (userName == null)
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    int retValue = db.ExecuteNonQuery(dbCommand);

    return retValue;


I need to check if connection is open then close



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We can learn or know how can we connect the database from our .net. This will help for freshers or .NET beginners!

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ASP.NET provides a configuration system we can use to keep our applications flexible at runtime. In this article we will examine some tips and best practices for using the configuration system for the best results.

The element of a web.config file is a place to store connection strings, server names, file paths, and other miscellaneous settings needed by an application to perform work. The items inside appSettings are items that need to be configurable depending upon the environment, for instance, any database connection strings will change as you move your application from a testing and staging server into production.

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How can I fix it?

connection to SQL Server files (*.mdf) require SQL server express 2005 to function properly.


I dont have the SQL EXPRESS installed instead I have SQL Standard Edition.

 I have two SQL Server instances installed.

 1- UserLT (this is sql 2000)
2- UserLT\SQL2005 (this is SQL 2005 named instance)

But when i try to add a database to my VS website project I get the following error:

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I went in Tools>Opetions>DataBase tools>Data Connection>Sql Server Instance Name (blank for default)

and changed the "SQLEXPRESS" to "USERLT\SQL2005".

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Unable to make connection to database?


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Need Oracle Data Provider .CS File for Oracle 10g Database connection !



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I'm getting an intermittant error:

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using System;
using System.Configuration;
using System.Configuration.Install;
using System.ComponentModel;
using System.Diagnostics;
using System.IO;
using System.DirectoryServices;

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