Question

I am writing my C# application that connects to database, does couple selects and then inserts record back to the server in the network.

But I have around 40k records and my program processes one records like for 1 second.

I don’t know how to improve the performance. Here are my sql getter and inserter. Any suggestions?

    public bool insert_and_ConfirmSQL(String Query, String comments)
    {
        bool success = false;
        NpgsqlCommand cmd = new NpgsqlCommand();
        NpgsqlConnection mycon = new NpgsqlConnection();
        string connstring = String.Format("Server={0};Port={1}; User Id={2};Password={3};Database={4};", tbHost, tbPort, tbUser, tbPass, tbDataBaseName);
        mycon.ConnectionString = connstring;
        cmd = mycon.CreateCommand();
        cmd.CommandText = Query;
        mycon.Open();

        int temp = 0;
        try
        {
            temp = cmd.ExecuteNonQuery();
            success = true;
        }
        catch
        {
            success = false;
        }
        finally
        {
            if (mycon.State.ToString() == "Open")
            {
                mycon.Close();
            }
        }
        return success;
    }


    public String getString(String sql, NpgsqlConnection conn)
    {
        using (DataSet ds = new DataSet())
        {
            using (NpgsqlDataAdapter da = new NpgsqlDataAdapter(sql, conn))
            {
                da.Fill(ds);
                if (ds.Tables.Count > 0)
                {
                    DataTable dt = ds.Tables[0];
                    //  check count of Rows 
                    if (dt.Rows.Count > 0)
                    {
                        object o = dt.Rows[0][0];
                        if (o != DBNull.Value && o != null)
                        {
                            return o.ToString();
                        }
                    }
                }
            }
        }
        // Return default value 
        return "";
    }

Answer 1

Sometimes you can improve performance by using a sql Datareader instead of DataSets.

http://msdn.microsoft.com/en-us/library/system.data.sqlclient.sqldatareader(v=vs.100).aspx#Y0

You then can Inspect the data while you are reading it from the database.

So I’d implement the above code with a DataReader and retime it.

Edit: Especially that getString method. if that ds.Fill was taking 40k rows that could be the cause of your performance problem.