Note: This API is now obsolete.
Represents an open connection to a database. This class cannot be inherited.
Assembly: System.Data.OracleClient (in System.Data.OracleClient.dll)
Thetype exposes the following members.
|ConnectionString||Gets or sets the string used to open an Oracle database. (Overrides DbConnection.ConnectionString.)|
|ConnectionTimeout||Gets the time to wait to establish a connection before terminating the attempt and generating an error. (Overrides DbConnection.ConnectionTimeout.)|
|Container||Gets the IContainer that contains the Component. (Inherited from Component.)|
|Database||Gets the name of the current database or the database to be used after a connection is opened. (Overrides DbConnection.Database.)|
|DataSource||Gets the name of the Oracle server to which to connect. (Overrides DbConnection.DataSource.)|
|ServerVersion||Gets a string containing the version of the server to which the client is connected. (Overrides DbConnection.ServerVersion.)|
|Site||Gets or sets the ISite of the Component. (Inherited from Component.)|
|State||Gets the current state of the connection. (Overrides DbConnection.State.)|
|BeginTransaction||Begins a transaction at the database.|
|BeginTransaction(IsolationLevel)||Begins a transaction at the database with the specified IsolationLevel value.|
|ChangeDatabase||Changes the current database for an open . (Overrides DbConnection.ChangeDatabase(String).)|
|ClearAllPools||Empties the connection pool.|
|ClearPool||Empties the connection pool associated with the specified connection.|
|Close||Closes the connection to the database. (Overrides DbConnection.Close.)|
|CreateCommand||Creates and returns an OracleCommand object associated with the .|
|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.)|
|Dispose||Releases all resources used by the Component. (Inherited from Component.)|
|EnlistDistributedTransaction||Enlists in the specified transaction as a distributed transaction.|
|EnlistTransaction||Enlists in the specified transaction as a distributed transaction. (Overrides DbConnection.EnlistTransaction(Transaction).)|
|Equals(Object)||Determines whether the specified object is equal to the current object. (Inherited from Object.)|
|GetHashCode||Serves as the default hash function. (Inherited from Object.)|
|GetLifetimeService||Retrieves the current lifetime service object that controls the lifetime policy for this instance. (Inherited from MarshalByRefObject.)|
|GetSchema||Returns schema information for the data source of this . (Overrides DbConnection.GetSchema.)|
|GetSchema(String)||Returns schema information for the data source of this using the specified string for the schema name. (Overrides DbConnection.GetSchema(String).)|
|GetSchema(String, String())||Returns schema information for the data source of this using the specified string for the schema name and the specified string array for the restriction values. (Overrides DbConnection.GetSchema(String, String()).)|
|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.)|
|Open||Opens a connection to a database with the property settings specified by the ConnectionString. (Overrides DbConnection.Open.)|
|OpenAsync||An asynchronous version of Open, which opens a database connection with the settings specified by the ConnectionString. This method invokes the virtual method OpenAsync with CancellationToken.None. (Inherited from DbConnection.)|
|OpenAsync(CancellationToken)||This is the asynchronous version of Open. Providers should override with an appropriate implementation. The cancellation token can optionally be honored.The default implementation invokes the synchronous Open call and returns a completed task. The default implementation will return a cancelled task if passed an already cancelled cancellationToken. Exceptions thrown by Open will be communicated via the returned Task Exception property.Do not invoke other methods and properties of the DbConnection object until the returned Task is complete. (Inherited from DbConnection.)|
|ToString||Returns a String containing the name of the Component, if any. This method should not be overridden. (Inherited from Component.)|
|ICloneable.Clone||Creates a new object that is a copy of the current instance.|
|IDbConnection.BeginTransaction||Begins a database transaction. (Inherited from DbConnection.)|
|IDbConnection.BeginTransaction(IsolationLevel)||Begins a database transaction with the specified IsolationLevel value. (Inherited from DbConnection.)|
|IDbConnection.CreateCommand||Creates and returns a DbCommand object that is associated with the current connection. (Inherited from DbConnection.)|
This type is deprecated and will be removed in a future version of the .NET Framework. For more information, see Oracle and ADO.NET.
An object represents a unique connection to an Oracle database. In the case of a client/server database system, it is equivalent to a network connection to the server.
An application that creates an instance of the object can set declarative or imperative security demands that require all direct and indirect callers to have adequate permission to the code. creates security demands by using the OraclePermission object. Users can verify that their code has adequate permissions by using the OraclePermissionAttribute object. Users and administrators can also use the Code Access Security Policy Tool (Caspol.exe) to modify security policy at the machine, user, and enterprise levels. For more information, see Security in the .NET Framework.
Unlike the Connection object in the other .NET Framework data providers (SQL Server, OLE DB, and ODBC), does not support a ConnectionTimeout property. Setting a connection time-out either as a property or in the connection string has no effect, and the value returned is always zero. also does not support a Database property or a ChangeDatabase method.
If the object goes out of scope, it remains open. Therefore, you should always close objects by calling Close or Dispose, or by using the object within a Using statement. Otherwise, the garbage collection might not free them immediately. Such delays can cause errors if the maximum number of connections is reached while a number of connections are waiting to be deleted by the garbage collector. By contrast, closing the connections by calling Close uses native resources more efficiently, enhancing scalability and improving overall application performance. To ensure that connections are always closed, open the connection inside of a Using block.
To deploy high-performance applications, you often need to use connection pooling. However, when you use the .NET Framework Data Provider for Oracle, you do not need to enable connection pooling because the provider manages this automatically.
The following example creates an OracleCommand and an . The is opened and set as the OracleCommand.Connection property. The example then calls ExecuteNonQuery, and closes the connection. To accomplish this, the ExecuteNonQuery is passed a connection string and a query string that is an SQL INSERT statement.
Public Sub InsertRow(ByVal connectionString As String) Dim queryString As String = _ "INSERT INTO Dept (DeptNo, Dname, Loc) values (50, 'TECHNOLOGY', 'DENVER')" Using connection As New OracleConnection(connectionString) Dim command As New OracleCommand(queryString) command.Connection = connection Try connection.Open() command.ExecuteNonQuery() Catch ex As Exception Console.WriteLine(ex.Message) End Try End Using End Sub