SqlCommand Class
Represents a Transact-SQL statement or stored procedure to execute against a SQL Server database. This class cannot be inherited.
System.MarshalByRefObject
System.ComponentModel.Component
System.Data.Common.DbCommand
System.Data.SqlClient.SqlCommand
Namespace: System.Data.SqlClient
Assembly: System.Data (in System.Data.dll)
The SqlCommand type exposes the following members.
| Name | Description | |
|---|---|---|
 | SqlCommand() | Initializes a new instance of the SqlCommand class. |
| SqlCommand(String) | Initializes a new instance of the SqlCommand class with the text of the query. |
| SqlCommand(String, SqlConnection) | Initializes a new instance of the SqlCommand class with the text of the query and a SqlConnection. |
| SqlCommand(String, SqlConnection, SqlTransaction) | Initializes a new instance of the SqlCommand class with the text of the query, a SqlConnection, and the SqlTransaction. |
| Name | Description | |
|---|---|---|
| CommandText | Gets or sets the Transact-SQL statement, table name or stored procedure to execute at the data source. (Overrides DbCommand.CommandText.) |
| CommandTimeout | Gets or sets the wait time before terminating the attempt to execute a command and generating an error. (Overrides DbCommand.CommandTimeout.) |
| CommandType | Gets or sets a value indicating how the CommandText property is to be interpreted. (Overrides DbCommand.CommandType.) |
| Connection | Gets or sets the SqlConnection used by this instance of the SqlCommand. |
| Container | Gets the IContainer that contains the Component. (Inherited from Component.) |
| DesignTimeVisible | Gets or sets a value indicating whether the command object should be visible in a Windows Form Designer control. (Overrides DbCommand.DesignTimeVisible.) |
| Notification | Gets or sets a value that specifies the SqlNotificationRequest object bound to this command. |
| NotificationAutoEnlist | Gets or sets a value indicating whether the application should automatically receive query notifications from a common SqlDependency object. |
| Parameters | Gets the SqlParameterCollection. |
| Site | Gets or sets the ISite of the Component. (Inherited from Component.) |
| Transaction | Gets or sets the SqlTransaction within which the SqlCommand executes. |
| UpdatedRowSource | Gets or sets how command results are applied to the DataRow when used by the Update method of the DbDataAdapter. (Overrides DbCommand.UpdatedRowSource.) |
| Name | Description | |
|---|---|---|
| BeginExecuteNonQuery() | Initiates the asynchronous execution of the Transact-SQL statement or stored procedure that is described by this SqlCommand. |
| BeginExecuteNonQuery(AsyncCallback, Object) | Initiates the asynchronous execution of the Transact-SQL statement or stored procedure that is described by this SqlCommand, given a callback procedure and state information. |
| BeginExecuteReader() | Initiates the asynchronous execution of the Transact-SQL statement or stored procedure that is described by this SqlCommand, and retrieves one or more result sets from the server. |
| BeginExecuteReader(CommandBehavior) | Initiates the asynchronous execution of the Transact-SQL statement or stored procedure that is described by this SqlCommand using one of the CommandBehavior values. |
| BeginExecuteReader(AsyncCallback, Object) | Initiates the asynchronous execution of the Transact-SQL statement or stored procedure that is described by this SqlCommand and retrieves one or more result sets from the server, given a callback procedure and state information. |
| BeginExecuteReader(AsyncCallback, Object, CommandBehavior) | Initiates the asynchronous execution of the Transact-SQL statement or stored procedure that is described by this SqlCommand, using one of the CommandBehavior values, and retrieving one or more result sets from the server, given a callback procedure and state information. |
| BeginExecuteXmlReader() | Initiates the asynchronous execution of the Transact-SQL statement or stored procedure that is described by this SqlCommand and returns results as an XmlReader object. |
| BeginExecuteXmlReader(AsyncCallback, Object) | Initiates the asynchronous execution of the Transact-SQL statement or stored procedure that is described by this SqlCommand and returns results as an XmlReader object, using a callback procedure. |
| Cancel | Tries to cancel the execution of a SqlCommand. (Overrides DbCommand.Cancel().) |
| Clone | Creates a new SqlCommand object that is a copy of the current instance. |
| 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 a SqlParameter object. |
| Dispose() | Releases all resources used by the Component. (Inherited from Component.) |
| EndExecuteNonQuery | Finishes asynchronous execution of a Transact-SQL statement. |
| EndExecuteReader | Finishes asynchronous execution of a Transact-SQL statement, returning the requested SqlDataReader. |
| EndExecuteXmlReader | Finishes asynchronous execution of a Transact-SQL statement, returning the requested data as XML. |
| Equals(Object) | Determines whether the specified object is equal to the current object. (Inherited from Object.) |
| ExecuteNonQuery | Executes a Transact-SQL statement against the connection and returns the number of rows affected. (Overrides DbCommand.ExecuteNonQuery().) |
| ExecuteNonQueryAsync() | An asynchronous version of ExecuteNonQuery, which executes a SQL statement against a connection object.Invokes ExecuteNonQueryAsync with CancellationToken.None. (Inherited from DbCommand.) |
| ExecuteNonQueryAsync(CancellationToken) | An asynchronous version of ExecuteNonQuery, which executes a Transact-SQL statement against the connection and returns the number of rows affected. The cancellation token can be used to request that the operation be abandoned before the command timeout elapses. Exceptions will be reported via the returned Task object. (Overrides DbCommand.ExecuteNonQueryAsync(CancellationToken).) |
| ExecuteReader() | Sends the CommandText to the Connection and builds a SqlDataReader. |
| ExecuteReader(CommandBehavior) | Sends the CommandText to the Connection, and builds a SqlDataReader using one of the CommandBehavior values. |
| ExecuteReaderAsync() | An asynchronous version of ExecuteReader, which sends the CommandText to the Connection and builds a SqlDataReader. Exceptions will be reported via the returned Task object. |
| ExecuteReaderAsync(CancellationToken) | An asynchronous version of ExecuteReader, which sends the CommandText to the Connection and builds a SqlDataReader.The cancellation token can be used to request that the operation be abandoned before the command timeout elapses. Exceptions will be reported via the returned Task object. |
| ExecuteReaderAsync(CommandBehavior) | An asynchronous version of ExecuteReader, which sends the CommandText to the Connection, and builds a SqlDataReader. Exceptions will be reported via the returned Task object. |
| ExecuteReaderAsync(CommandBehavior, CancellationToken) | An asynchronous version of ExecuteReader, which sends the CommandText to the Connection, and builds a SqlDataReaderThe cancellation token can be used to request that the operation be abandoned before the command timeout elapses. Exceptions will be reported via the returned Task object. |
| 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().) |
| ExecuteScalarAsync() | An asynchronous version of ExecuteScalar, which executes the query and returns the first column of the first row in the result set returned by the query. All other columns and rows are ignored.Invokes ExecuteScalarAsync with CancellationToken.None. (Inherited from DbCommand.) |
| ExecuteScalarAsync(CancellationToken) | An asynchronous version of ExecuteScalar, which executes the query asynchronously and returns the first column of the first row in the result set returned by the query. Additional columns or rows are ignored.The cancellation token can be used to request that the operation be abandoned before the command timeout elapses. Exceptions will be reported via the returned Task object. (Overrides DbCommand.ExecuteScalarAsync(CancellationToken).) |
| ExecuteXmlReader | Sends the CommandText to the Connection and builds an XmlReader object. |
| ExecuteXmlReaderAsync() | An asynchronous version of ExecuteXmlReader, which sends the CommandText to the Connection and builds an XmlReader object.Exceptions will be reported via the returned Task object. |
| ExecuteXmlReaderAsync(CancellationToken) | An asynchronous version of ExecuteXmlReader, which sends the CommandText to the Connection and builds an XmlReader object.The cancellation token can be used to request that the operation be abandoned before the command timeout elapses. Exceptions will be reported via the returned Task object. |
| 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.) |
| 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.) |
| Prepare | Creates a prepared version of the command on an instance of SQL Server. (Overrides DbCommand.Prepare().) |
| ResetCommandTimeout | Resets the CommandTimeout property to its default value. |
| ToString | Returns a String containing the name of the Component, if any. This method should not be overridden. (Inherited from Component.) |
| Name | Description | |
|---|---|---|
| Disposed | Occurs when the component is disposed by a call to the Dispose method. (Inherited from Component.) |
| StatementCompleted | Occurs when the execution of a Transact-SQL statement completes. |
| Name | Description | |
|---|---|---|
| ICloneable.Clone | Creates a new SqlCommand object that is a copy of the current instance. |
 | 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() | 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 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.) |
When an instance of SqlCommand is created, the read/write properties are set to their initial values. For a list of these values, see the SqlCommand constructor.
SqlCommand features the following methods for executing commands at a SQL Server database:
Item | Description |
|---|---|
Initiates the asynchronous execution of the Transact-SQL statement or stored procedure that is described by this SqlCommand, generally executing commands such as INSERT, DELETE, UPDATE, and SET statements. Each call to BeginExecuteNonQuery must be paired with a call to EndExecuteNonQuery which finishes the operation, typically on a separate thread. | |
Initiates the asynchronous execution of the Transact-SQL statement or stored procedure that is described by this SqlCommand and retrieves one or more results sets from the server. Each call to BeginExecuteReader must be paired with a call to EndExecuteReader which finishes the operation, typically on a separate thread. | |
Initiates the asynchronous execution of the Transact-SQL statement or stored procedure that is described by this SqlCommand. Each call to BeginExecuteXmlReader must be paired with a call to EndExecuteXmlReader, which finishes the operation, typically on a separate thread, and returns an XmlReader object. | |
Executes commands that return rows. For increased performance, ExecuteReader invokes commands using the Transact-SQL sp_executesql system stored procedure. Therefore, ExecuteReader might not have the effect that you want if used to execute commands such as Transact-SQL SET statements. | |
Executes commands such as Transact-SQL INSERT, DELETE, UPDATE, and SET statements. | |
Retrieves a single value (for example, an aggregate value) from a database. | |
Sends the CommandText to the Connection and builds an XmlReader object. |
You can reset the CommandText property and reuse the SqlCommand object. However, you must close the SqlDataReader before you can execute a new or previous command.
If a SqlException is generated by the method executing a SqlCommand, the SqlConnection remains open when the severity level is 19 or less. When the severity level is 20 or greater, the server ordinarily closes the SqlConnection. However, the user can reopen the connection and continue.
| Note |
|---|
Nameless, also called ordinal, parameters are not supported by the .NET Framework Data Provider for SQL Server. |
| Topic | Location |
|---|---|
| Walkthrough: Displaying Hierarchical Data in a TreeView Control | Building ASP .NET Web Applications in Visual Studio |
The following example creates a SqlConnection, a SqlCommand, and a SqlDataReader. The example reads through the data, writing it to the console. Finally, the example closes the SqlDataReader and then the SqlConnection as it exits the Using code blocks.
private static void ReadOrderData(string connectionString) { string queryString = "SELECT OrderID, CustomerID FROM dbo.Orders;"; using (SqlConnection connection = new SqlConnection( connectionString)) { SqlCommand command = new SqlCommand( queryString, connection); connection.Open(); SqlDataReader reader = command.ExecuteReader(); try { while (reader.Read()) { Console.WriteLine(String.Format("{0}, {1}", reader[0], reader[1])); } } finally { // Always call Close when done reading. reader.Close(); } } }
Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
