Represents an SQL statement or stored procedure to execute against a data source.
Namespace: System.Data.OleDb
Assembly: System.Data (in system.data.dll)
Visual Basic (Declaration)
Public NotInheritable Class OleDbCommand
Inherits DbCommand
Implements ICloneable, IDbCommand, IDisposable
Dim instance As OleDbCommand
public sealed class OleDbCommand : DbCommand, ICloneable, IDbCommand, IDisposable
public ref class OleDbCommand sealed : public DbCommand, ICloneable, IDbCommand, IDisposable
public final class OleDbCommand extends DbCommand implements ICloneable, IDbCommand,
IDisposable
public final class OleDbCommand extends DbCommand implements ICloneable, IDbCommand,
IDisposable
When an instance of OleDbCommand is created, the read/write properties are set to their initial values. For a list of these values, see the OleDbCommand constructor.
OleDbCommand features the following methods executing commands at a data source:
| Item | Description |
| ExecuteReader | Executes commands that return rows. ExecuteReader may not have the effect that you want if used to execute commands such as SQL SET statements. |
| ExecuteNonQuery | Executes commands such as SQL INSERT, DELETE, UPDATE, and SET statements. |
| ExecuteScalar | Retrieves a single value, for example, an aggregate value from a database. |
You can reset the CommandText property and reuse the OleDbCommand object. However, you must close the OleDbDataReader before you can execute a new or previous command.
If a fatal OleDbException (for example, a SQL Server severity level of 20 or greater) is generated by the method executing an OleDbCommand, the OleDbConnection, the connection may be closed. However, the user can reopen the connection and continue.
The following example uses the OleDbCommand, along OleDbDataAdapter and OleDbConnection, to select rows from an Access database. The filled DataSet is then returned. The example is passed an initialized DataSet, a connection string, a query string that is an SQL SELECT statement, and a string that is the name of the source database table.
Public Sub ReadMyData(ByVal connectionString As String)
Dim queryString As String = "SELECT OrderID, CustomerID FROM Orders"
Using connection As New OleDbConnection(connectionString)
Dim command As New OleDbCommand(queryString, connection)
connection.Open()
Dim reader As OleDbDataReader = command.ExecuteReader()
While reader.Read()
Console.WriteLine(reader.GetInt32(0).ToString() + ", " _
+ reader.GetString(1))
End While
' always call Close when done reading.
reader.Close()
End Using
End Sub
public void ReadMyData(string connectionString)
{
string queryString = "SELECT OrderID, CustomerID FROM Orders";
using (OleDbConnection connection = new OleDbConnection(connectionString))
{
OleDbCommand command = new OleDbCommand(queryString, connection);
connection.Open();
OleDbDataReader reader = command.ExecuteReader();
while (reader.Read())
{
Console.WriteLine(reader.GetInt32(0) + ", " + reader.GetString(1));
// always call Close when done reading.
reader.Close();
using System;
using System.Data;
using System.Data.OleDb;
class Class1
{
static void Main()
{
public void ReadMyData(string connectionString)
{
string queryString = "SELECT OrderID, CustomerID FROM Orders";
using (OleDbConnection connection = new OleDbConnection(connectionString))
{
OleDbCommand command = new OleDbCommand(queryString, connection);
connection.Open();
OleDbDataReader reader = command.ExecuteReader();
while (reader.Read())
{
Console.WriteLine(reader.GetInt32(0) + ", " + reader.GetString(1));
// always call Close when done reading.
reader.Close();
System.Object
System.MarshalByRefObject
System.ComponentModel.Component
System.Data.Common.DbCommand
System.Data.OleDb.OleDbCommand
Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
Windows 98, Windows 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see System Requirements.
.NET Framework
Supported in: 2.0, 1.1, 1.0