This document summarizes how to connect to a SQL database and retrieve data using ADO.NET in C#. It explains that a DataTable collects rows and columns from a database, and a SqlCommand specifies the query and database connection. A SqlDataAdapter fetches data from the connection and query into the DataTable. Both DataSet and DataTable retrieve table structure and rows from a database, but DataSet fetches multiple rows at a time while DataTable fetches single rows. An example demonstrates creating a DataTable, SqlConnection, SqlCommand, and SqlDataAdapter to execute a query and fill the DataTable.

1. Sql connection

2. DataTable
• Datatable it is a Collection of Database Rows and Columns
Example : DataTable dt = new DataTable("Student");

3. Sqlcommand
• In this Scenario Sql Command Acts to point database location and
database query
Connection String and sql query
Example :
string query = "Select * from Table";
• SqlConnection con = new SqlConnection();
• con.ConnectionString = "Data Source=(localdb)MSSQLLocalDB;Initial Catalog=ChartDB;Integrated Security=True";
• SqlCommand cmd = new SqlCommand();
• cmd.CommandText = query;
• cmd.Connection = con;

4. SqlDataAdapter
• SqlDataAdapter
Finally SqlDataAdapter fetch into Connection & Sqlquery send back to
Datatable

5. DataSet
• DataSet Which has Currently Strored Single DataBase Table, and Get
Entire Table structure of Rows and colums in a DataBase Table
• DataSet Fetches multiple row at a time

6. DataTable
• DataTable Which has Currently Strored Single DataBase Table, and Get
Entire Table structure of Rows and colums in a DataBase Table
• Datatable Fetches single row at a time

7. Example :
DataTable dt = new DataTable("Student");
string query = "Select * from Table";
SqlConnection con = new SqlConnection();
con.ConnectionString = "Data Source=(localdb)MSSQLLocalDB;Initial Catalog=ChartDB;Integrated Security=True";
SqlCommand cmd = new SqlCommand();
cmd.CommandText = query;
cmd.Connection = con;
SqlDataAdapter da = new SqlDataAdapter(cmd);
con.Open();
da.Fill(dt);
con.Close();
return dt;

8. THANK YOU