MySqlCommand Class

MySQL Connector/Net

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MySQL Connector/Net

MySqlCommand Class

Represents a SQL statement to execute against a MySQL database. This class cannot be inherited.

Inheritance Hierarchy

SystemObject  SystemMarshalByRefObject
    System.ComponentModelComponent
      System.Data.CommonDbCommand
        MySql.Data.MySqlClientMySqlCommand

Namespace: MySql.Data.MySqlClient
Assembly: MySql.Data (in MySql.Data.dll) Version: 6.9.9

Syntax

C++

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public sealed class MySqlCommand : DbCommand, 
	ICloneable, IDisposable

Public NotInheritable Class MySqlCommand
	Inherits DbCommand
	Implements ICloneable, IDisposable

public ref class MySqlCommand sealed : public DbCommand, 
	ICloneable, IDisposable

[<SealedAttribute>]
type MySqlCommand =  
    class
        inherit DbCommand
        interface ICloneable
        interface IDisposable
    end

The MySqlCommand type exposes the following members.

Constructors

	Name	Description
	MySqlCommand	Initializes a new instance of the MySqlCommand class.
	MySqlCommand(String)	Initializes a new instance of the MySqlCommand class with the text of the query.
	MySqlCommand(String, MySqlConnection)	Initializes a new instance of the MySqlCommand class with the text of the query and a MySqlConnection.
	MySqlCommand(String, MySqlConnection, MySqlTransaction)	Initializes a new instance of the MySqlCommand class with the text of the query, a MySqlConnection, and the MySqlTransaction.

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Properties

	Name	Description
	CacheAge
	CanRaiseEvents	Gets a value indicating whether the component can raise an event. (Inherited from Component.)
	CommandText	Gets or sets the SQL statement to execute at the data source. (Overrides DbCommandCommandText.)
	CommandTimeout	Gets or sets the wait time before terminating the attempt to execute a command and generating an error. (Overrides DbCommandCommandTimeout.)
	CommandType	Gets or sets a value indicating how the CommandText property is to be interpreted. (Overrides DbCommandCommandType.)
	Connection	Gets or sets the MySqlConnection used by this instance of the MySqlCommand.
	Container	Gets the IContainer that contains the Component. (Inherited from Component.)
	DbConnection	(Overrides DbCommandDbConnection.)
	DbParameterCollection	(Overrides DbCommandDbParameterCollection.)
	DbTransaction	(Overrides DbCommandDbTransaction.)
	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 Windows Form Designer control. (Overrides DbCommandDesignTimeVisible.)
	EnableCaching
	Events	Gets the list of event handlers that are attached to this Component. (Inherited from Component.)
	IsPrepared
	LastInsertedId
	Parameters	Get the MySqlParameterCollection
	Site	Gets or sets the ISite of the Component. (Inherited from Component.)
	Transaction	Gets or sets the MySqlTransaction within which the MySqlCommand executes.
	UpdatedRowSource	Gets or sets how command results are applied to the DataRow when used by the Update method of the DbDataAdapter. (Overrides DbCommandUpdatedRowSource.)

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Methods

	Name	Description
	BeginExecuteNonQuery	Initiates the asynchronous execution of the SQL statement or stored procedure that is described by this MySqlCommand.
	BeginExecuteNonQuery(AsyncCallback, Object)	Initiates the asynchronous execution of the SQL statement or stored procedure that is described by this MySqlCommand.
	BeginExecuteReader	Initiates the asynchronous execution of the SQL statement or stored procedure that is described by this MySqlCommand, and retrieves one or more result sets from the server.
	BeginExecuteReader(CommandBehavior)	Initiates the asynchronous execution of the SQL statement or stored procedure that is described by this MySqlCommand using one of the CommandBehavior values.
	Cancel	Attempts to cancel the execution of a currently active command (Overrides DbCommandCancel.)
	Clone	Creates a clone of this MySqlCommand object. CommandText, Connection, and Transaction properties are included as well as the entire parameter list.
	CreateDbParameter	(Overrides DbCommandCreateDbParameter.)
	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 MySqlParameter object.
	Dispose
	Dispose(Boolean)	(Overrides ComponentDispose(Boolean).)
	EndExecuteNonQuery	Finishes asynchronous execution of a SQL statement.
	EndExecuteReader	Finishes asynchronous execution of a SQL statement, returning the requested MySqlDataReader.
	Equals	Determines whether the specified object is equal to the current object. (Inherited from Object.)
	ExecuteDbDataReader	(Overrides DbCommandExecuteDbDataReader(CommandBehavior).)
	ExecuteDbDataReaderAsync	(Inherited from DbCommand.)
	ExecuteNonQuery	Executes a SQL statement against the connection and returns the number of rows affected. (Overrides DbCommandExecuteNonQuery.)
	ExecuteNonQueryAsync	(Inherited from DbCommand.)
	ExecuteNonQueryAsync(CancellationToken)	(Inherited from DbCommand.)
	ExecuteReader	Sends the CommandText to the Connection and builds a MySqlDataReader.
	ExecuteReader(CommandBehavior)	Sends the CommandText to the Connection, and builds a MySqlDataReader using one of the CommandBehavior values.
	ExecuteReaderAsync	(Inherited from DbCommand.)
	ExecuteReaderAsync(CancellationToken)	(Inherited from DbCommand.)
	ExecuteReaderAsync(CommandBehavior)	(Inherited from DbCommand.)
	ExecuteReaderAsync(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. Extra columns or rows are ignored. (Overrides DbCommandExecuteScalar.)
	ExecuteScalarAsync	(Inherited from DbCommand.)
	ExecuteScalarAsync(CancellationToken)	(Inherited from DbCommand.)
	Finalize	(Overrides ComponentFinalize.)
	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.)
	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 version of the command on an instance of MySQL Server. (Overrides DbCommandPrepare.)
	ToString	Returns a String containing the name of the Component, if any. This method should not be overridden. (Inherited from Component.)

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Events

	Name	Description
	Disposed	Occurs when the component is disposed by a call to the Dispose method. (Inherited from Component.)

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Remarks

MySqlCommand features the following methods for executing commands at a MySQL database:

Item	Description
ExecuteReader	Executes commands that return rows.
ExecuteNonQuery	Executes commands such as SQL INSERT, DELETE, and UPDATE statements.
ExecuteScalar	Retrieves a single value (for example, an aggregate value) from a database.

You can reset the CommandText property and reuse the MySqlCommand object. However, you must close the MySqlDataReader before you can execute a new or previous command. If a MySqlException is generated by the method executing a MySqlCommand, the MySqlConnection remains open. It is the responsibility of the programmer to close the connection.

Note
Using the '@' symbol for paramters is now the preferred approach although the old pattern of using '?' is still supported. Please be aware though that using '@' can cause conflicts when user variables are also used. To help with this situation please see the documentation on the 'allow user variables' connection string option. The 'old syntax' connection string option has now been deprecated.

Examples

The following example creates a MySqlCommand and a MySqlConnection. The MySqlConnection is opened and set as the Connection for the MySqlCommand. 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 a SQL INSERT statement.

C++

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public void InsertRow(string myConnectionString)
{
// If the connection string is null, use a default.
if(myConnectionString == "")
{
myConnectionString = "Database=Test;Data Source=localhost;User Id=username;Password=pass";
}
MySqlConnection myConnection = new MySqlConnection(myConnectionString);
string myInsertQuery = "INSERT INTO Orders (id, customerId, amount) Values(1001, 23, 30.66)";
MySqlCommand myCommand = new MySqlCommand(myInsertQuery);
myCommand.Connection = myConnection;
myConnection.Open();
myCommand.ExecuteNonQuery();
myCommand.Connection.Close();
}

Public Sub InsertRow(myConnectionString As String)
" If the connection string is null, use a default.
If myConnectionString = "" Then
myConnectionString = "Database=Test;Data Source=localhost;User Id=username;Password=pass"
End If
Dim myConnection As New MySqlConnection(myConnectionString)
Dim myInsertQuery As String = "INSERT INTO Orders (id, customerId, amount) Values(1001, 23, 30.66)"
Dim myCommand As New MySqlCommand(myInsertQuery)
myCommand.Connection = myConnection
myConnection.Open()
myCommand.ExecuteNonQuery()
myCommand.Connection.Close()
End Sub

No code example is currently available or this language may not be supported.

Reference

MySql.Data.MySqlClient Namespace

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