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OracleCommand Class

Definition

Caution

OracleCommand has been deprecated. http://go.microsoft.com/fwlink/?LinkID=144260

Represents an SQL statement or stored procedure to execute against a database. This class cannot be inherited.

public sealed class OracleCommand : System.ComponentModel.Component, ICloneable, IDisposable, System.Data.IDbCommand
public sealed class OracleCommand : System.Data.Common.DbCommand, ICloneable
[System.Obsolete("OracleCommand has been deprecated. http://go.microsoft.com/fwlink/?LinkID=144260", false)]
public sealed class OracleCommand : System.Data.Common.DbCommand, ICloneable
Inheritance
Inheritance
Attributes
Implements

Examples

The following example uses the ExecuteReader method of OracleCommand, along with OracleDataReader and OracleConnection, to select rows from a table.

public void ReadMyData(string connectionString)
{
    string queryString = "SELECT EmpNo, DeptNo FROM Scott.Emp";
    using (OracleConnection connection = new OracleConnection(connectionString))
    {
        OracleCommand command = new OracleCommand(queryString, connection);
        connection.Open();
        OracleDataReader reader = command.ExecuteReader();
        try
        {
            while (reader.Read())
            {
                Console.WriteLine(reader.GetInt32(0) + ", " + reader.GetInt32(1));
            }
        }
        finally
        {
            // always call Close when done reading.
            reader.Close();
        }
    }
}

Remarks

This type is deprecated and will be removed in a future version of the .NET Framework. For more information, see Oracle and ADO.NET.

The OracleCommand class provides the following methods for executing commands against a data source:

Item Description
ExecuteReader Executes commands that return rows.
ExecuteOracleNonQuery Executes an SQL statement against the Connection and returns the number of rows affected.
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 as a .NET Framework data type.
ExecuteOracleScalar Retrieves a single value (for example, an aggregate value) from a database as an Oracle-specific data type.

You can reset the CommandText property and reuse the OracleCommand object.

If execution of the command results in a fatal OracleException, the OracleConnection may close. However, the user can reopen the connection and continue.

Megjegyzés

Unlike the Command object in the other .NET Framework data providers (SQL Server, OLE DB, and ODBC), the OracleCommand object does not support a CommandTimeout property. Setting a command timeout has no effect and the value returned is always zero.

Constructors

OracleCommand()

Initializes a new instance of the OracleCommand.

OracleCommand(String, OracleConnection, OracleTransaction)

Initializes a new instance of the OracleCommand class with the text of the query, an OracleConnection object, and an OracleTransaction.

OracleCommand(String, OracleConnection)

Initializes a new instance of the OracleCommand class with the text of the query and an OracleConnection object.

OracleCommand(String)

Initializes a new instance of the OracleCommand class with the text of the query.

Properties

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 against the database.

CommandTimeout

Gets or sets the wait time (in seconds) before terminating the attempt to execute a command and generating an error.

CommandType

Gets or sets a value indicating how the CommandText property is interpreted.

Connection

Gets or sets the OracleConnection used by this instance of the OracleCommand.

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 indicating whether the command object should be visible in a customized interface control.

Events

Gets the list of event handlers that are attached to this Component.

(Inherited from Component)
Parameters

Gets the OracleParameterCollection.

Site

Gets or sets the ISite of the Component.

(Inherited from Component)
Transaction

Gets or sets the OracleTransaction within which the OracleCommand executes.

UpdatedRowSource

Gets or sets a value that specifies how the Update method should apply command results to the DataRow.

Methods

Cancel()

Attempts to cancel the execution of an OracleCommand.

Clone()

Creates a copy of this OracleCommand object.

CreateDbParameter()

Creates a new instance of a DbParameter object.

(Inherited from DbCommand)
CreateObjRef(Type)

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 OracleParameter object.

Dispose()

Releases all resources used by the Component.

(Inherited from Component)
Dispose()

Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.

(Inherited from DbCommand)
Dispose(Boolean)

Releases the unmanaged resources used by the Component and optionally releases the managed resources.

(Inherited from Component)
Dispose(Boolean)

Releases the unmanaged resources used by the DbCommand and optionally releases the managed resources.

(Inherited from DbCommand)
DisposeAsync()

Asynchronously diposes the command object.

(Inherited from DbCommand)
Equals(Object)

Determines whether the specified object is equal to the current object.

(Inherited from Object)
ExecuteDbDataReader(CommandBehavior)

Executes the command against its connection, returning a DbDataReader which can be used to access the results.

(Inherited from DbCommand)
ExecuteDbDataReaderAsync(CommandBehavior, CancellationToken)

Providers should implement this method to provide a non-default implementation for ExecuteReader overloads.

The default implementation invokes the synchronous ExecuteReader() method and returns a completed task, blocking the calling thread. The default implementation will return a cancelled task if passed an already cancelled cancellation token. Exceptions thrown by ExecuteReader will be communicated via the returned Task Exception property.

This method accepts a cancellation token that can be used to request the operation to be cancelled early. Implementations may ignore this request.

(Inherited from DbCommand)
ExecuteNonQuery()

Executes an SQL statement against the Connection and returns the number of rows affected.

ExecuteNonQueryAsync()

An asynchronous version of ExecuteNonQuery(), which executes the command against its connection object, returning the number of rows affected.

Invokes ExecuteNonQueryAsync(CancellationToken) with CancellationToken.None.

(Inherited from DbCommand)
ExecuteNonQueryAsync(CancellationToken)

This is the asynchronous version of ExecuteNonQuery(). Providers should override with an appropriate implementation. The cancellation token may optionally be ignored.

The default implementation invokes the synchronous ExecuteNonQuery() method and returns a completed task, blocking the calling thread. The default implementation will return a cancelled task if passed an already cancelled cancellation token. Exceptions thrown by ExecuteNonQuery() will be communicated via the returned Task Exception property.

Do not invoke other methods and properties of the DbCommand object until the returned Task is complete.

(Inherited from DbCommand)
ExecuteOracleNonQuery(OracleString)

Executes an SQL statement against the Connection and returns the number of rows affected.

ExecuteOracleScalar()

Executes the query, and returns the first column of the first row in the result set returned by the query as an Oracle-specific data type. Extra columns or rows are ignored.

ExecuteReader()

Sends the CommandText to the Connection and builds an OracleDataReader.

ExecuteReader(CommandBehavior)

Sends the CommandText to the Connection, and builds an OracleDataReader using one of the CommandBehavior values.

ExecuteReaderAsync()

An asynchronous version of ExecuteReader, which executes the command against its connection, returning a DbDataReader which can be used to access the results.

Invokes ExecuteDbDataReaderAsync(CommandBehavior, CancellationToken) with CancellationToken.None.

(Inherited from DbCommand)
ExecuteReaderAsync(CancellationToken)

An asynchronous version of ExecuteReader, which executes the command against its connection, returning a DbDataReader which can be used to access the results.

Invokes ExecuteDbDataReaderAsync(CommandBehavior, CancellationToken).

(Inherited from DbCommand)
ExecuteReaderAsync(CommandBehavior, CancellationToken)

Invokes ExecuteDbDataReaderAsync(CommandBehavior, CancellationToken).

(Inherited from DbCommand)
ExecuteReaderAsync(CommandBehavior)

An asynchronous version of ExecuteReader, which executes the command against its connection, returning a DbDataReader which can be used to access the results.

Invokes ExecuteDbDataReaderAsync(CommandBehavior, CancellationToken).

(Inherited from DbCommand)
ExecuteScalar()

Executes the query, and returns the first column of the first row in the result set returned by the query as a .NET data type. Extra columns or rows are ignored.

ExecuteScalarAsync()

An asynchronous version of ExecuteScalar(), which executes the command and returns the first column of the first row in the first returned result set. All other columns, rows and result sets are ignored.

Invokes ExecuteScalarAsync(CancellationToken) with CancellationToken.None.

(Inherited from DbCommand)
ExecuteScalarAsync(CancellationToken)

This is the asynchronous version of ExecuteScalar(). Providers should override with an appropriate implementation. The cancellation token may optionally be ignored.

The default implementation invokes the synchronous ExecuteScalar() method and returns a completed task, blocking the calling thread. The default implementation will return a cancelled task if passed an already cancelled cancellation token. Exceptions thrown by ExecuteScalar will be communicated via the returned Task Exception property.

Do not invoke other methods and properties of the DbCommand object until the returned Task is complete.

(Inherited from DbCommand)
GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetLifetimeService()
Obsolete.

Retrieves the current lifetime service object that controls the lifetime policy for this instance.

(Inherited from MarshalByRefObject)
GetService(Type)

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()
Obsolete.

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 at the data source.

PrepareAsync(CancellationToken)

Asynchronously creates a prepared (or compiled) version of the command on the data source.

(Inherited from DbCommand)
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)

Events

Disposed

Occurs when the component is disposed by a call to the Dispose() method.

(Inherited from Component)

Explicit Interface Implementations

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.

IDbCommand.CreateParameter()

Creates a new instance of an IDbDataParameter object.

(Inherited from DbCommand)
IDbCommand.ExecuteReader()

Executes the CommandText against the Connection and builds an IDataReader.

IDbCommand.ExecuteReader()

Executes the CommandText against the Connection and builds an IDataReader.

(Inherited from DbCommand)
IDbCommand.ExecuteReader(CommandBehavior)

Executes the CommandText against the Connection, and builds an IDataReader by using one of the CommandBehavior values.

IDbCommand.ExecuteReader(CommandBehavior)

Executes the CommandText against the Connection, and builds an IDataReader using one of the CommandBehavior values.

(Inherited from DbCommand)
IDbCommand.Parameters

Gets the IDataParameterCollection.

(Inherited from DbCommand)
IDbCommand.Transaction

Gets or sets the DbTransaction within which this DbCommand object executes.

(Inherited from DbCommand)

Applies to

Termék Verziók (Elavult)
.NET Framework 1.1, 2.0, 3.0, 3.5 (4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1)

See also