How to fill Dataset with multiple tables?

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小鲜肉
小鲜肉 2020-11-29 07:20

I\'m trying to fill DataSet which contains 2 tables with one to many relationship. I\'m using DataReader to achieve this :

    public DataSet SelectOne(int i         


        
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  • 2020-11-29 07:53

    If you are issuing a single command with several select statements, you might use NextResult method to move to next resultset within the datareader: http://msdn.microsoft.com/en-us/library/system.data.idatareader.nextresult.aspx

    I show how it could look bellow:

    public DataSet SelectOne(int id)
    {
        DataSet result = new DataSet();
        using (DbCommand command = Connection.CreateCommand())
        {
            command.CommandText = @"
    select * from table1
    select * from table2
            ";
    
            var param = ParametersBuilder.CreateByKey(command, "ID", id, null);
            command.Parameters.Add(param);
    
            Connection.Open();
            using (DbDataReader reader = command.ExecuteReader())
            {
                result.MainTable.Load(reader);
                reader.NextResult();
                result.SecondTable.Load(reader);
                // ...
            }
            Connection.Close();
        }
        return result;
    }
    
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  • 2020-11-29 07:57

    It is an old topic, but for some people it might be useful:

            DataSet someDataSet = new DataSet();
            SqlDataAdapter adapt = new SqlDataAdapter();
    
            using(SqlConnection connection = new SqlConnection(ConnString))
            {
                connection.Open();
                SqlCommand comm1 = new SqlCommand("SELECT * FROM whateverTable", connection);
                SqlCommand comm2g = new SqlCommand("SELECT * FROM whateverTable WHERE condition = @0", connection);
                commProcessing.Parameters.AddWithValue("@0", "value");
                someDataSet.Tables.Add("Table1");
                someDataSet.Tables.Add("Table2");
    
                adapt.SelectCommand = comm1;
                adapt.Fill(someDataSet.Tables["Table1"]);
                adapt.SelectCommand = comm2;
                adapt.Fill(someDataSet.Tables["Table2"]);
            }
    
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  • 2020-11-29 08:00
    public DataSet GetDataSet()
        {
            try
            {
                DataSet dsReturn = new DataSet();
                using (SqlConnection myConnection = new SqlConnection(Core.con))
                {
                    string query = "select * from table1;  select* from table2";
                    SqlCommand cmd = new SqlCommand(query, myConnection);
                    myConnection.Open();
                    SqlDataReader reader = cmd.ExecuteReader();
                    dsReturn.Load(reader, LoadOption.PreserveChanges, new string[] { "tableOne", "tableTwo" });
                    return dsReturn;
                }
            }
            catch (Exception)
            {
                throw;
            }
        }
    
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  • 2020-11-29 08:07
    protected void Page_Load(object sender, EventArgs e)
    {
        SqlConnection con = new SqlConnection("data source=.;uid=sa;pwd=123;database=shop");
        //SqlCommand cmd = new SqlCommand("select * from tblemployees", con);
        //SqlCommand cmd1 = new SqlCommand("select * from tblproducts", con);
        //SqlDataAdapter da = new SqlDataAdapter();
    
        //DataSet ds = new DataSet();
        //ds.Tables.Add("emp");
        //ds.Tables.Add("products");
        //da.SelectCommand = cmd;
        //da.Fill(ds.Tables["emp"]);
        //da.SelectCommand = cmd1;
    
        //da.Fill(ds.Tables["products"]);
        SqlDataAdapter da = new SqlDataAdapter("select * from tblemployees", con);
        DataSet ds = new DataSet();
        da.Fill(ds, "em");
        da = new SqlDataAdapter("select * from tblproducts", con);
        da.Fill(ds, "prod");
    
        GridView1.DataSource = ds.Tables["em"];
        GridView1.DataBind();
        GridView2.DataSource = ds.Tables["prod"];
        GridView2.DataBind();
    }
    
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  • 2020-11-29 08:09

    Filling a DataSet with multiple tables can be done by sending multiple requests to the database, or in a faster way: Multiple SELECT statements can be sent to the database server in a single request. The problem here is that the tables generated from the queries have automatic names Table and Table1. However, the generated table names can be mapped to names that should be used in the DataSet.

    SqlDataAdapter adapter = new SqlDataAdapter(
          "SELECT * FROM Customers; SELECT * FROM Orders", connection);
    adapter.TableMappings.Add("Table", "Customer");
    adapter.TableMappings.Add("Table1", "Order");
    
    adapter.Fill(ds);
    
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  • 2020-11-29 08:12
             string connetionString = null;
            SqlConnection connection ;
            SqlCommand command ;
            SqlDataAdapter adapter = new SqlDataAdapter();
            DataSet ds = new DataSet();
            int i = 0;
            string firstSql = null;
            string secondSql = null;
    
            connetionString = "Data Source=ServerName;Initial Catalog=DatabaseName;User ID=UserName;Password=Password";
            firstSql = "Your First SQL Statement Here";
            secondSql = "Your Second SQL Statement Here";
            connection = new SqlConnection(connetionString);
    
            try
            {
                connection.Open();
    
                command = new SqlCommand(firstSql, connection);
                adapter.SelectCommand = command;
                adapter.Fill(ds, "First Table");
    
                adapter.SelectCommand.CommandText = secondSql;
                adapter.Fill(ds, "Second Table");
    
                adapter.Dispose();
                command.Dispose();
                connection.Close();
    
                //retrieve first table data 
                for (i = 0; i <= ds.Tables[0].Rows.Count - 1; i++)
                {
                    MessageBox.Show(ds.Tables[0].Rows[i].ItemArray[0] + " -- " + ds.Tables[0].Rows[i].ItemArray[1]);
                }
                //retrieve second table data 
                for (i = 0; i <= ds.Tables[1].Rows.Count - 1; i++)
                {
                    MessageBox.Show(ds.Tables[1].Rows[i].ItemArray[0] + " -- " + ds.Tables[1].Rows[i].ItemArray[1]);
    
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show("Can not open connection ! ");
            }
    
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