using System;
using System.Data.OleDb;
public class ReadFromOleDb
{
[STAThread]
static void Main(string[] args)
{
String sConn = "provider=sqloledb;server=(local)SQLEXPRESS;database=MyDatabase;Integrated Security=SSPI";
String sSQL = "select id, firstname, lastname from Employee";
OleDbConnection oConn = new OleDbConnection(sConn);
oConn.Open();
OleDbCommand oCmd = new OleDbCommand(sSQL, oConn);
OleDbDataReader oReader = oCmd.ExecuteReader();
int idxID = oReader.GetOrdinal("id");
int idxFirstName = oReader.GetOrdinal("firstname");
int idxLastName = oReader.GetOrdinal("lastname");
while(oReader.Read()) {
Console.WriteLine("{0} {1} {2}",
oReader.GetValue(idxID),
oReader.GetValue(idxFirstName),
oReader.GetValue(idxLastName));
}
}
}
Read value using OleDbDataReader
using System;
using System.Data;
using System.Data.OleDb;
public class Prepare {
public static void Main () {
String connect = "Provider=Microsoft.JET.OLEDB.4.0;data source=.Employee.mdb";
OleDbConnection con = new OleDbConnection(connect);
con.Open();
Console.WriteLine("Made the connection to the database");
OleDbCommand cmd2 = con.CreateCommand();
cmd2.CommandText = "SELECT First_name FROM Employee "
+ "WHERE ID > ?";
OleDbParameter p3 = new OleDbParameter();
cmd2.Parameters.Add(p3);
p3.Value = new Decimal(0.0);
OleDbDataReader reader = cmd2.ExecuteReader();
while(reader.Read())
Console.WriteLine("{0}", reader.GetString(0));
reader.Close();
con.Close();
}
}
Execute complicated SQL query
using System;
using System.Data;
using System.Data.OleDb;
public class ExtractInfo {
public static void Main () {
String connect = "Provider=Microsoft.JET.OLEDB.4.0;data source=.Employee.mdb";
OleDbConnection con = new OleDbConnection(connect);
con.Open();
Console.WriteLine("Made the connection to the Sales database");
OleDbCommand cmd = con.CreateCommand();
cmd.CommandText = "SELECT DISTINCT CustomerName "
+ "FROM Customer, Item, Orders, OrderItem "
+ "WHERE Customer.CustomerID = Orders.CustomerID "
+ "AND Orders.OrderNumber = OrderItem.OrderNumber "
+ "AND OrderItem.ItemNumber = Item.ItemNumber "
+ "AND Description = 'computer'";
OleDbDataReader reader = cmd.ExecuteReader();
while(reader.Read())
Console.WriteLine(reader.GetString(0));
reader.Close();
con.Close();
}
}
Read result set containing all columns
using System;
using System.Data;
using System.Data.OleDb;
public class ExtractInfo {
public static void Main () {
String connect = "Provider=Microsoft.JET.OLEDB.4.0;data source=.Employee.mdb";
OleDbConnection con = new OleDbConnection(connect);
con.Open();
Console.WriteLine("Made the connection to the Sales database");
OleDbCommand cmd = con.CreateCommand();
cmd.CommandText = "SELECT * FROM Employee";
OleDbDataReader reader = cmd.ExecuteReader();
Console.WriteLine();
Console.WriteLine("ID FirstName LastName Salary");
while (reader.Read())
Console.WriteLine("{0} {1} {2} {3}",reader.GetInt32(0),reader.GetString(1),reader.GetString(2), reader.GetDecimal(3));
reader.Close();
con.Close();
}
}
Query more columns and read result set
using System;
using System.Data;
using System.Data.OleDb;
public class ExtractInfo {
public static void Main () {
String connect = "Provider=Microsoft.JET.OLEDB.4.0;data source=.Employee.mdb";
OleDbConnection con = new OleDbConnection(connect);
con.Open();
Console.WriteLine("Made the connection to the Sales database");
OleDbCommand cmd = con.CreateCommand();
cmd.CommandText = "SELECT First_Name, Last_Name FROM Employee ORDER BY First_Name";
OleDbDataReader reader = cmd.ExecuteReader();
Console.WriteLine("First_Name Last_Name");
while(reader.Read())
Console.WriteLine("{0} {1}",reader.GetString(0), reader.GetString(1));
reader.Close();
con.Close();
}
}
OleDbConnection: ServerVersion
using System;
using System.Data;
using System.Data.SqlClient;
using System.Data.OleDb;
class MainClass {
public static void Main() {
using (OleDbConnection con = new OleDbConnection()) {
con.ConnectionString = "Provider=SQLOLEDB;" +
@"Data Source=.sqlexpress;" +
"Initial Catalog=Northwind;" +
"Integrated Security=SSPI";
con.Open();
if (con.State == ConnectionState.Open) {
Console.WriteLine(" Server Version = " + con.ServerVersion);
} else {
Console.WriteLine("OleDbConnection failed to open.");
Console.WriteLine(" Connection State = " + con.State);
}
}
}
}
OleDbConnection: Database
using System;
using System.Data;
using System.Data.SqlClient;
using System.Data.OleDb;
class MainClass {
public static void Main() {
using (OleDbConnection con = new OleDbConnection()) {
con.ConnectionString = "Provider=SQLOLEDB;" +
@"Data Source=.sqlexpress;" +
"Initial Catalog=Northwind;" +
"Integrated Security=SSPI";
con.Open();
if (con.State == ConnectionState.Open) {
Console.WriteLine(" Database = " + con.Database);
} else {
Console.WriteLine("OleDbConnection failed to open.");
Console.WriteLine(" Connection State = " + con.State);
}
}
}
}

