Filling Dataset by executing query on multiple tables

Question

Dear Friends
I have a problem. I want to fill dataset by executing query on multiple tables and then capture data in comboboxes.
and also combox1.datasource=ds.tables["which table name or what should i write here?"]

Suresh Paldia · Answer

Why don't you execute a JOIN on multiple tables returning a single dataset. Example: String query = SELECT A.firstname FROM EMPLOYEETABLE AS A INNER/LEFT/RIGHT/FULL JOIN ADDRESSTABLE AS B ON somecondition; SqlDataAdapter a = new SqlDataAdapter(querycon); DataSet ds = new DataSet(); a.Fill(dsresulttable); ComboBox1.DataSource = ds;

Suresh Paldia · Answer

Your Welcome Mayur..

Suresh Paldia · Answer

Your welcome Mayur

Mayur Gujrathi · Answer

Thank You Very Much Sir

Suresh Paldia · Answer

In above case when using join and if the result returned is only one datatable. This datatable your dataset is known by name resulttable if i use a.Fill(dsresulttable); Now in future you can refer/map to that table by using ComboBox1.DataSource = ds.Table[resulttable] But in case my query itself is returning more than 1 tables for example string stmt = SELECT name FROM Customer SELECT ordernumber FROM Order SELECT recieptnumber FROM RecieveDetails; Or you might use a stored procedure that returns multiple tables. Code above will result in 3 DataTables called Table Table1 Table2 by default if i use - a.Fill(ds); ComboBox1.DataSource = ds.Tables[Table]; ComboBox2.DataSource = ds.Tables[Table1]; ComboBox3.DataSource = ds.Tables[Table2]; And it will return 3 datatables called resulttable resulttable1 and resulttable2 if i use - a.Fill(dsresulttable); ComboBox1.DataSource = ds.Tables[resulttable]; ComboBox2.DataSource = ds.Tables[resulttable1]; ComboBox3.DataSource = ds.Tables[resulttable2]; Accordingly you will have to refer these tables by these names only. But i recommend you to add a TableMapping for each table returned by your statement. You can do this as SqlDataAdapter da= new SqlDataAdapter(stmt sqlConnection); da.TableMappings.Add(Table Customer); da.TableMappings.Add(Table1 Order); da.TableMappings.Add(Table2 RecieveDetails); da.Fill(dataset); Then you can use; ComboBox1.DataSource = ds.Tables[Customer]; ComboBox2.DataSource = ds.Tables[Order]; ComboBox3.DataSource = ds.Tables[RecieveDetails]; More meaningful... isn't it! Hope you got this concept... For more about Table Mapping you can visit http://msdn.microsoft.com/en-us/library/ms810286.aspx Happy Learning...

Mayur Gujrathi · Answer

Sir Whats This resulttable. Please give me some brief exposureIts Urgent. I didnt understood Thank You String query = SELECT A.firstname FROM EMPLOYEETABLE AS A INNER/LEFT/RIGHT/FULL JOIN ADDRESSTABLE AS B ON somecondition; SqlDataAdapter a = new SqlDataAdapter(querycon); DataSet ds = new DataSet(); a.Fill(dsresulttable); ComboBox1.DataSource = ds;

Manikavelu Velayutham · Answer

You can achieve your goal using LINQ. There you can join multiple table and fetch the needed values. Finally you can fill it in a dataset.

Mahesh Chand · Answer

Are these tables are related? If these tables are related data should automatically come in multiple DataTable objects within a singe DataSet. To access a table you can specify the table name. For example if you have two tables - Customer and Products. comboBox1.DataSource = ds.Tables[Customers]; So what you need to do is either create a relationship in your database and use the JOIN SQL query OR you can add a relationship in the DataRelation (you probably don't need this).