Represents an SQL statement or stored procedure to execute against a data source.
Assembly: System.Data (in System.Data.dll)
Thetype exposes the following members.
|OleDbCommand||Initializes a new instance of the class.|
|OleDbCommand(String)||Initializes a new instance of the class with the text of the query.|
|OleDbCommand(String, OleDbConnection)||Initializes a new instance of the class with the text of the query and an OleDbConnection.|
|OleDbCommand(String, OleDbConnection, OleDbTransaction)||Initializes a new instance of the class with the text of the query, an OleDbConnection, and the Transaction.|
|CanRaiseEvents||Gets a value indicating whether the component can raise an event. (Inherited from Component.)|
|CommandText||Gets or sets the SQL statement or stored procedure to execute at the data source. (Overrides DbCommand.CommandText.)|
|CommandTimeout||Gets or sets the wait time before terminating an attempt to execute a command and generating an error. (Overrides DbCommand.CommandTimeout.)|
|CommandType||Gets or sets a value that indicates how the CommandText property is interpreted. (Overrides DbCommand.CommandType.)|
|Connection||Gets or sets the OleDbConnection used by this instance of the .|
|Container||Gets the IContainer that contains the Component. (Inherited from Component.)|
|DbConnection||Gets or sets the DbConnection used by this DbCommand. (Inherited from DbCommand.)|
|DbParameterCollection||Gets the collection of DbParameter objects. (Inherited from DbCommand.)|
|DbTransaction||Gets or sets the DbTransaction within which this DbCommand object executes. (Inherited from DbCommand.)|
|DesignMode||Gets a value that indicates whether the Component is currently in design mode. (Inherited from Component.)|
|DesignTimeVisible||Gets or sets a value that indicates whether the command object should be visible in a customized Windows Forms Designer control. (Overrides DbCommand.DesignTimeVisible.)|
|Events||Gets the list of event handlers that are attached to this Component. (Inherited from Component.)|
|Parameters||Gets the OleDbParameterCollection.|
|Site||Gets or sets the ISite of the Component. (Inherited from Component.)|
|Transaction||Gets or sets the OleDbTransaction within which the executes.|
|UpdatedRowSource||Gets or sets how command results are applied to the DataRow when used by the Update method of the OleDbDataAdapter. (Overrides DbCommand.UpdatedRowSource.)|
|Cancel||Tries to cancel the execution of an . (Overrides DbCommand.Cancel.)|
|Clone||Creates a new object that is a copy of the current instance.|
|CreateDbParameter||Creates a new instance of a DbParameter object. (Inherited from DbCommand.)|
|CreateObjRef||Creates an object that contains all the relevant information required to generate a proxy used to communicate with a remote object. (Inherited from MarshalByRefObject.)|
|CreateParameter||Creates a new instance of an OleDbParameter object.|
|Dispose||Releases all resources used by the Component. (Inherited from Component.)|
|Dispose(Boolean)||Releases the unmanaged resources used by the Component and optionally releases the managed resources. (Inherited from Component.)|
|Equals(Object)||Determines whether the specified Object is equal to the current Object. (Inherited from Object.)|
|ExecuteDbDataReader||Executes the command text against the connection. (Inherited from DbCommand.)|
|ExecuteNonQuery||Executes an SQL statement against the Connection and returns the number of rows affected. (Overrides DbCommand.ExecuteNonQuery.)|
|ExecuteReader||Sends the CommandText to the Connection and builds an OleDbDataReader.|
|ExecuteReader(CommandBehavior)||Sends the CommandText to the Connection, and builds an OleDbDataReader using one of the CommandBehavior values.|
|ExecuteScalar||Executes the query, and returns the first column of the first row in the result set returned by the query. Additional columns or rows are ignored. (Overrides DbCommand.ExecuteScalar.)|
|Finalize||Releases unmanaged resources and performs other cleanup operations before the Component is reclaimed by garbage collection. (Inherited from Component.)|
|GetHashCode||Serves as a hash function for a particular type. (Inherited from Object.)|
|GetLifetimeService||Retrieves the current lifetime service object that controls the lifetime policy for this instance. (Inherited from MarshalByRefObject.)|
|GetService||Returns an object that represents a service provided by the Component or by its Container. (Inherited from Component.)|
|GetType||Gets the Type of the current instance. (Inherited from Object.)|
|InitializeLifetimeService||Obtains a lifetime service object to control the lifetime policy for this instance. (Inherited from MarshalByRefObject.)|
|MemberwiseClone||Creates a shallow copy of the current Object. (Inherited from Object.)|
|MemberwiseClone(Boolean)||Creates a shallow copy of the current MarshalByRefObject object. (Inherited from MarshalByRefObject.)|
|Prepare||Creates a prepared (or compiled) version of the command on the data source. (Overrides DbCommand.Prepare.)|
|ResetCommandTimeout||Resets the CommandTimeout property to the default value.|
|ToString||Returns a String containing the name of the Component, if any. This method should not be overridden. (Inherited from Component.)|
|ICloneable.Clone||For a description of this member, see ICloneable.Clone.|
|IDbCommand.Connection||Gets or sets the IDbConnection used by this instance of the IDbCommand. (Inherited from DbCommand.)|
|IDbCommand.CreateParameter||Creates a new instance of an IDbDataParameter object. (Inherited from DbCommand.)|
|IDbCommand.ExecuteReader||For a description of this member, see IDbCommand.ExecuteReader.|
|IDbCommand.ExecuteReader(CommandBehavior)||Executes the CommandText against the Connection, and builds an IDataReader using one of the CommandBehavior values.|
|IDbCommand.Parameters||Gets the IDataParameterCollection. (Inherited from DbCommand.)|
|IDbCommand.Transaction||Gets or sets the DbTransaction within which this DbCommand object executes. (Inherited from DbCommand.)|
When an instance of is created, the read/write properties are set to their initial values. For a list of these values, see the constructor.
features the following methods executing commands at a data source:
Executes commands that return rows. ExecuteReader may not have the effect that you want if used to execute commands such as SQL SET statements.
Executes commands such as SQL INSERT, DELETE, UPDATE, and SET statements.
Retrieves a single value, for example, an aggregate value from a database.
If a fatal OleDbException (for example, a SQL Server severity level of 20 or greater) is generated by the method executing an , the OleDbConnection, the connection may be closed. However, the user can reopen the connection and continue.
The following example uses the , 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
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.