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OleDbCommand Class

Represents an SQL statement or stored procedure to execute against a data source.

Namespace:  System.Data.OleDb
Assembly:  System.Data (in System.Data.dll)

'Declaration
Public NotInheritable Class OleDbCommand _
	Inherits DbCommand _
	Implements ICloneable, IDbCommand, IDisposable
'Usage
Dim instance As OleDbCommand

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

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 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

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