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); } } } }