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The next generation of the Teknik Services. Written in ASP.NET. https://www.teknik.io/
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Teknik/Teknik/docs/MySqlCommand.xml

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<docs>
<ClassSummary>
<summary>Represents a SQL statement to execute against a MySQL database. This class cannot be inherited.</summary>
<remarks>
<B>MySqlCommand</B> features the following methods for executing commands at a MySQL database:
<list type="table">
<listheader>
<term>Item</term>
<term>Description</term>
</listheader>
<item>
<term>
<a href="MySql.Data.MySqlClient.MySqlCommand.ExecuteReader_overloads.html">ExecuteReader</a>
</term>
<description>Executes commands that return rows.</description>
</item>
<item>
<term>
<a href="MySql.Data.MySqlClient.MySqlCommand.ExecuteNonQuery.html">ExecuteNonQuery</a>
</term>
<description>Executes commands such as SQL INSERT, DELETE, and UPDATE statements.</description>
</item>
<item>
<term>
<a href="MySql.Data.MySqlClient.MySqlCommand.ExecuteScalar.html">ExecuteScalar</a>
</term>
<description>Retrieves a single value (for example, an aggregate value) from a database.</description>
</item>
</list>
You can reset the <B>CommandText</B> property and reuse the <B>MySqlCommand</B>
object. However, you must close the <A
href="MySql.Data.MySqlClient.MySqlDataReader.html">MySqlDataReader</A>
before you can execute a new or previous command.
If a <A href="MySql.Data.MySqlClient.MySqlException.html">MySqlException</A> is
generated by the method executing a <B>MySqlCommand</B>, the <A
href="MySql.Data.MySqlClient.MySqlConnection.html">MySqlConnection</A>
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.
</note>
</remarks>
<example>
The following example creates a <A href="frlrfsystemdatasqlclientsqlcommandclasstopic.htm">MySqlCommand</A> and
a <B>MySqlConnection</B>. The <B>MySqlConnection</B> is opened and set as the <A
href="frlrfsystemdatasqlclientsqlcommandclassconnectiontopic.htm">Connection</A>
for the <B>MySqlCommand</B>. The example then calls <A
href="frlrfsystemdatasqlclientsqlcommandclassexecutenonquerytopic.htm">ExecuteNonQuery</A>,
and closes the connection. To accomplish this, the <B>ExecuteNonQuery</B> is
passed a connection string and a query string that is a SQL INSERT
statement.
<code lang="vbnet">
Public Sub InsertRow(myConnectionString As String)
&quot; 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
</code>
<code lang="C#">
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();
}
</code>
</example>
</ClassSummary>
<ctor1>
<overloads>
<summary>
Initializes a new instance of the MySqlCommand class.
</summary>
<example>
The following example creates a MySqlCommand and sets some of its properties.
<para></para>
<note>
This example shows how to use one of the overloaded
versions of the MySqlCommand constructor. For other examples that might be available,
see the individual overload topics.
</note>
<code lang="vbnet">
Public Sub CreateMySqlCommand()
Dim myConnection As New MySqlConnection _
("Persist Security Info=False;database=test;server=myServer")
myConnection.Open()
Dim myTrans As MySqlTransaction = myConnection.BeginTransaction()
Dim mySelectQuery As String = "SELECT * FROM MyTable"
Dim myCommand As New MySqlCommand(mySelectQuery, myConnection, myTrans)
myCommand.CommandTimeout = 20
End Sub
</code>
<code lang="C#">
public void CreateMySqlCommand()
{
MySqlConnection myConnection = new MySqlConnection("Persist Security Info=False;
database=test;server=myServer");
myConnection.Open();
MySqlTransaction myTrans = myConnection.BeginTransaction();
string mySelectQuery = "SELECT * FROM myTable";
MySqlCommand myCommand = new MySqlCommand(mySelectQuery, myConnection,myTrans);
myCommand.CommandTimeout = 20;
}
</code>
<code lang="C++">
public:
void CreateMySqlCommand()
{
MySqlConnection* myConnection = new MySqlConnection(S"Persist Security Info=False;
database=test;server=myServer");
myConnection->Open();
MySqlTransaction* myTrans = myConnection->BeginTransaction();
String* mySelectQuery = S"SELECT * FROM myTable";
MySqlCommand* myCommand = new MySqlCommand(mySelectQuery, myConnection, myTrans);
myCommand->CommandTimeout = 20;
};
</code>
</example>
</overloads>
<summary>
Initializes a new instance of the MySqlCommand class.
</summary>
<remarks>
The base constructor initializes all fields to their default values. The
following table shows initial property values for an instance of <see cref="MySqlCommand"/>.
<list type="table">
<listheader>
<term>Properties</term>
<term>Initial Value</term>
</listheader>
<item>
<term>
<see cref="CommandText"/>
</term>
<term>empty string ("")</term>
</item>
<item>
<term>
<see cref="CommandTimeout"/>
</term>
<term>0</term>
</item>
<item>
<term>
<see cref="CommandType"/>
</term>
<term>CommandType.Text</term>
</item>
<item>
<term>
<see cref="Connection"/>
</term>
<term>Null</term>
</item>
</list>
<para>
You can change the value for any of these properties through a separate call to
the property.
</para>
</remarks>
<example>
The following example creates a <see cref="MySqlCommand"/> and
sets some of its properties.
<code lang="vbnet">
Public Sub CreateMySqlCommand()
Dim myCommand As New MySqlCommand()
myCommand.CommandType = CommandType.Text
End Sub
</code>
<code lang="C#">
public void CreateMySqlCommand()
{
MySqlCommand myCommand = new MySqlCommand();
myCommand.CommandType = CommandType.Text;
}
</code>
</example>
</ctor1>
<ctor2>
<summary>
Initializes a new instance of the <see cref="MySqlCommand"/> class with the text of the query.
</summary>
<param name="cmdText">The text of the query.</param>
<remarks>
When an instance of <see cref="MySqlCommand"/> is created,
the following read/write properties are set to initial values.
<list type="table">
<listheader>
<term>Properties</term>
<term>Initial Value</term>
</listheader>
<item>
<term>
<see cref="CommandText"/>
</term>
<term>
<i>cmdText</i>
</term>
</item>
<item>
<term>
<see cref="CommandTimeout"/>
</term>
<term>0</term>
</item>
<item>
<term>
<see cref="CommandType"/>
</term>
<term>CommandType.Text</term>
</item>
<item>
<term>
<see cref="Connection"/>
</term>
<term>Null</term>
</item>
</list>
<para>
You can change the value for any of these properties through a separate call to
the property.
</para>
</remarks>
<example>
The following example creates a <see cref="MySqlCommand"/> and
sets some of its properties.
<code lang="vbnet">
Public Sub CreateMySqlCommand()
Dim sql as String = "SELECT * FROM mytable"
Dim myCommand As New MySqlCommand(sql)
myCommand.CommandType = CommandType.Text
End Sub
</code>
<code lang="C#">
public void CreateMySqlCommand()
{
string sql = "SELECT * FROM mytable";
MySqlCommand myCommand = new MySqlCommand(sql);
myCommand.CommandType = CommandType.Text;
}
</code>
</example>
</ctor2>
<ctor3>
<summary>
Initializes a new instance of the <see cref="MySqlCommand"/> class
with the text of the query and a <see cref="MySqlConnection"/>.
</summary>
<param name="cmdText">The text of the query.</param>
<param name="connection">
A <see cref="MySqlConnection"/> that represents the
connection to an instance of SQL Server.
</param>
<remarks>
When an instance of <see cref="MySqlCommand"/> is created,
the following read/write properties are set to initial values.
<list type="table">
<listheader>
<term>Properties</term>
<term>Initial Value</term>
</listheader>
<item>
<term>
<see cref="CommandText"/>
</term>
<term>
<i>cmdText</i>
</term>
</item>
<item>
<term>
<see cref="CommandTimeout"/>
</term>
<term>0</term>
</item>
<item>
<term>
<see cref="CommandType"/>
</term>
<term>CommandType.Text</term>
</item>
<item>
<term>
<see cref="Connection"/>
</term>
<term>
<i>connection</i>
</term>
</item>
</list>
<para>
You can change the value for any of these properties through a separate call to
the property.
</para>
</remarks>
<example>
The following example creates a <see cref="MySqlCommand"/> and
sets some of its properties.
<code lang="vbnet">
Public Sub CreateMySqlCommand()
Dim conn as new MySqlConnection("server=myServer")
Dim sql as String = "SELECT * FROM mytable"
Dim myCommand As New MySqlCommand(sql, conn)
myCommand.CommandType = CommandType.Text
End Sub
</code>
<code lang="C#">
public void CreateMySqlCommand()
{
MySqlConnection conn = new MySqlConnection("server=myserver")
string sql = "SELECT * FROM mytable";
MySqlCommand myCommand = new MySqlCommand(sql, conn);
myCommand.CommandType = CommandType.Text;
}
</code>
</example>
</ctor3>
<ctor4>
<summary>
Initializes a new instance of the <see cref="MySqlCommand"/> class
with the text of the query, a <see cref="MySqlConnection"/>, and the
<see cref="MySqlTransaction"/>.
</summary>
<param name="cmdText">The text of the query.</param>
<param name="connection">
A <see cref="MySqlConnection"/> that represents the
connection to an instance of SQL Server.
</param>
<param name="transaction">
The <see cref="MySqlTransaction"/> in which the <see cref="MySqlCommand"/> executes.
</param>
<remarks>
When an instance of <see cref="MySqlCommand"/> is created,
the following read/write properties are set to initial values.
<list type="table">
<listheader>
<term>Properties</term>
<term>Initial Value</term>
</listheader>
<item>
<term>
<see cref="CommandText"/>
</term>
<term>
<i>cmdText</i>
</term>
</item>
<item>
<term>
<see cref="CommandTimeout"/>
</term>
<term>0</term>
</item>
<item>
<term>
<see cref="CommandType"/>
</term>
<term>CommandType.Text</term>
</item>
<item>
<term>
<see cref="Connection"/>
</term>
<term>
<i>connection</i>
</term>
</item>
</list>
<para>
You can change the value for any of these properties through a separate call to
the property.
</para>
</remarks>
<example>
The following example creates a <see cref="MySqlCommand"/> and
sets some of its properties.
<code lang="vbnet">
Public Sub CreateMySqlCommand()
Dim conn as new MySqlConnection("server=myServer")
conn.Open();
Dim txn as MySqlTransaction = conn.BeginTransaction()
Dim sql as String = "SELECT * FROM mytable"
Dim myCommand As New MySqlCommand(sql, conn, txn)
myCommand.CommandType = CommandType.Text
End Sub
</code>
<code lang="C#">
public void CreateMySqlCommand()
{
MySqlConnection conn = new MySqlConnection("server=myserver")
conn.Open();
MySqlTransaction txn = conn.BeginTransaction();
string sql = "SELECT * FROM mytable";
MySqlCommand myCommand = new MySqlCommand(sql, conn, txn);
myCommand.CommandType = CommandType.Text;
}
</code>
</example>
</ctor4>
<ExecuteNonQuery>
<summary>
Executes a SQL statement against the connection and returns the number of rows affected.
</summary>
<returns>Number of rows affected</returns>
<remarks>
You can use ExecuteNonQuery to perform any type of database operation,
however any resultsets returned will not be available. Any output parameters
used in calling a stored procedure will be populated with data and can be
retrieved after execution is complete.
For UPDATE, INSERT, and DELETE statements, the return value is the number
of rows affected by the command. For all other types of statements, the return
value is -1.
</remarks>
<example>
The following example creates a MySqlCommand and then
executes it using ExecuteNonQuery. The example is passed a string that is a
SQL statement (such as UPDATE, INSERT, or DELETE) and a string to use to
connect to the data source.
<code lang="vbnet">
Public Sub CreateMySqlCommand(myExecuteQuery As String, myConnection As MySqlConnection)
Dim myCommand As New MySqlCommand(myExecuteQuery, myConnection)
myCommand.Connection.Open()
myCommand.ExecuteNonQuery()
myConnection.Close()
End Sub
</code>
<code lang="C#">
public void CreateMySqlCommand(string myExecuteQuery, MySqlConnection myConnection)
{
MySqlCommand myCommand = new MySqlCommand(myExecuteQuery, myConnection);
myCommand.Connection.Open();
myCommand.ExecuteNonQuery();
myConnection.Close();
}
</code>
</example>
</ExecuteNonQuery>
<ExecuteReader1>
<summary>
Sends the <see cref="CommandText"/> to the <see cref="MySqlConnection">Connection</see>,
and builds a <see cref="MySqlDataReader"/> using one of the <see cref="CommandBehavior"/> values.
</summary>
<param name="behavior">
One of the <see cref="CommandBehavior"/> values.
</param>
<remarks>
<para>
When the <see cref="CommandType"/> property is set to <B>StoredProcedure</B>,
the <see cref="CommandText"/> property should be set to the name of the stored
procedure. The command executes this stored procedure when you call
<B>ExecuteReader</B>.
</para>
<para>
The <see cref="MySqlDataReader"/> supports a special mode that enables large binary
values to be read efficiently. For more information, see the <B>SequentialAccess</B>
setting for <see cref="CommandBehavior"/>.
</para>
<para>
While the <see cref="MySqlDataReader"/> is in use, the associated
<see cref="MySqlConnection"/> is busy serving the <B>MySqlDataReader</B>.
While in this state, no other operations can be performed on the
<B>MySqlConnection</B> other than closing it. This is the case until the
<see cref="MySqlDataReader.Close"/> method of the <B>MySqlDataReader</B> is called.
If the <B>MySqlDataReader</B> is created with <B>CommandBehavior</B> set to
<B>CloseConnection</B>, closing the <B>MySqlDataReader</B> closes the connection
automatically.
</para>
<note>
When calling ExecuteReader with the SingleRow behavior, you should be aware that using a <i>limit</i>
clause in your SQL will cause all rows (up to the limit given) to be retrieved by the client. The
<see cref="MySqlDataReader.Read"/> method will still return false after the first row but pulling all rows of data
into the client will have a performance impact. If the <i>limit</i> clause is not necessary, it should
be avoided.
</note>
</remarks>
<returns>
A <see cref="MySqlDataReader"/> object.
</returns>
</ExecuteReader1>
<ExecuteReader>
<summary>
Sends the <see cref="CommandText"/> to the <see cref="MySqlConnection">Connection</see>
and builds a <see cref="MySqlDataReader"/>.
</summary>
<returns>
A <see cref="MySqlDataReader"/> object.
</returns>
<remarks>
<para>
When the <see cref="CommandType"/> property is set to <B>StoredProcedure</B>,
the <see cref="CommandText"/> property should be set to the name of the stored
procedure. The command executes this stored procedure when you call
<B>ExecuteReader</B>.
</para>
<para>
While the <see cref="MySqlDataReader"/> is in use, the associated
<see cref="MySqlConnection"/> is busy serving the <B>MySqlDataReader</B>.
While in this state, no other operations can be performed on the
<B>MySqlConnection</B> other than closing it. This is the case until the
<see cref="MySqlDataReader.Close"/> method of the <B>MySqlDataReader</B> is called.
</para>
</remarks>
<example>
The following example creates a <see cref="MySqlCommand"/>, then executes it by
passing a string that is a SQL SELECT statement, and a string to use to connect to the
data source.
<code lang="vbnet">
Public Sub CreateMySqlDataReader(mySelectQuery As String, myConnection As MySqlConnection)
Dim myCommand As New MySqlCommand(mySelectQuery, myConnection)
myConnection.Open()
Dim myReader As MySqlDataReader
myReader = myCommand.ExecuteReader()
Try
While myReader.Read()
Console.WriteLine(myReader.GetString(0))
End While
Finally
myReader.Close
myConnection.Close
End Try
End Sub
</code>
<code lang="C#">
public void CreateMySqlDataReader(string mySelectQuery, MySqlConnection myConnection)
{
MySqlCommand myCommand = new MySqlCommand(mySelectQuery, myConnection);
myConnection.Open();
MMySqlDataReader myReader;
myReader = myCommand.ExecuteReader();
try
{
while(myReader.Read())
{
Console.WriteLine(myReader.GetString(0));
}
}
finally
{
myReader.Close();
myConnection.Close();
}
}
</code>
</example>
</ExecuteReader>
<Prepare>
<summary>
Creates a prepared version of the command on an instance of MySQL Server.
</summary>
<remarks>
<para>
Prepared statements are only supported on MySQL version 4.1 and higher. Calling
prepare while connected to earlier versions of MySQL will succeed but will execute
the statement in the same way as unprepared.
</para>
</remarks>
<example>
The following example demonstrates the use of the <b>Prepare</b> method.
<code lang="VB.NET">
public sub PrepareExample()
Dim cmd as New MySqlCommand("INSERT INTO mytable VALUES (@val)", myConnection)
cmd.Parameters.Add( "@val", 10 )
cmd.Prepare()
cmd.ExecuteNonQuery()
cmd.Parameters(0).Value = 20
cmd.ExecuteNonQuery()
end sub
</code>
<code lang="C#">
private void PrepareExample()
{
MySqlCommand cmd = new MySqlCommand("INSERT INTO mytable VALUES (@val)", myConnection);
cmd.Parameters.Add( "@val", 10 );
cmd.Prepare();
cmd.ExecuteNonQuery();
cmd.Parameters[0].Value = 20;
cmd.ExecuteNonQuery();
}
</code>
</example>
</Prepare>
<ExecuteScalar>
<summary>
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.
</summary>
<returns>
The first column of the first row in the result set, or a null reference if the
result set is empty
</returns>
<remarks>
<para>
Use the <B>ExecuteScalar</B> method to retrieve a single value (for example,
an aggregate value) from a database. This requires less code than using the
<see cref="ExecuteReader()"/> method, and then performing the operations necessary
to generate the single value using the data returned by a <see cref="MySqlDataReader"/>
</para>
</remarks>
<example>
The following example creates a <see cref="MySqlCommand"/> and then
executes it using <B>ExecuteScalar</B>. The example is passed a string that is a
SQL statement that returns an aggregate result, and a string to use to
connect to the data source.
<code lang="vbnet">
Public Sub CreateMySqlCommand(myScalarQuery As String, myConnection As MySqlConnection)
Dim myCommand As New MySqlCommand(myScalarQuery, myConnection)
myCommand.Connection.Open()
myCommand.ExecuteScalar()
myConnection.Close()
End Sub
</code>
<code lang="C#">
public void CreateMySqlCommand(string myScalarQuery, MySqlConnection myConnection)
{
MySqlCommand myCommand = new MySqlCommand(myScalarQuery, myConnection);
myCommand.Connection.Open();
myCommand.ExecuteScalar();
myConnection.Close();
}
</code>
<code lang="C++">
public:
void CreateMySqlCommand(String* myScalarQuery, MySqlConnection* myConnection)
{
MySqlCommand* myCommand = new MySqlCommand(myScalarQuery, myConnection);
myCommand-&gt;Connection-&gt;Open();
myCommand-&gt;ExecuteScalar();
myConnection-&gt;Close();
}
</code>
</example>
</ExecuteScalar>
<CommandText>
<summary>
Gets or sets the SQL statement to execute at the data source.
</summary>
<value>
The SQL statement or stored procedure to execute. The default is an empty string.
</value>
<remarks>
<para>
When the <see cref="CommandType"/> property is set to <B>StoredProcedure</B>,
the <B>CommandText</B> property should be set to the name of the stored procedure.
The user may be required to use escape character syntax if the stored procedure name
contains any special characters. The command executes this stored procedure when
you call one of the Execute methods. Starting with Connector/Net 5.0, having both a stored function
and stored procedure with the same name in the same database is not supported. It is
suggested that you provide unqiue names for your stored routines.
</para>
</remarks>
<example>
The following example creates a <see cref="MySqlCommand"/> and sets some of its properties.
<code lang="vbnet">
Public Sub CreateMySqlCommand()
Dim myCommand As New MySqlCommand()
myCommand.CommandText = "SELECT * FROM Mytable ORDER BY id"
myCommand.CommandType = CommandType.Text
End Sub
</code>
<code lang="C#">
public void CreateMySqlCommand()
{
MySqlCommand myCommand = new MySqlCommand();
myCommand.CommandText = "SELECT * FROM mytable ORDER BY id";
myCommand.CommandType = CommandType.Text;
}
</code>
</example>
</CommandText>
<CommandTimeout>
<summary>
Gets or sets the wait time before terminating the attempt to execute a command
and generating an error.
</summary>
<value>
The time (in seconds) to wait for the command to execute. The default is 30
seconds.
</value>
<remarks>
CommandTimeout is dependent on the ability of MySQL to cancel an executing query.
Because of this, CommandTimeout is only supported when connected to MySQL
version 5.0.0 or higher.
</remarks>
</CommandTimeout>
<CommandType>
<summary>
Gets or sets a value indicating how the <see cref="CommandText"/> property is to be interpreted.
</summary>
<value>
One of the <see cref="System.Data.CommandType"/> values. The default is <B>Text</B>.
</value>
<remarks>
<para>
When you set the <B>CommandType</B> property to <B>StoredProcedure</B>, you
should set the <see cref="CommandText"/> property to the name of the stored
procedure. The command executes this stored procedure when you call one of the
Execute methods.
</para>
</remarks>
<example>
The following example creates a <see cref="MySqlCommand"/> and sets some of its properties.
<code lang="vbnet">
Public Sub CreateMySqlCommand()
Dim myCommand As New MySqlCommand()
myCommand.CommandType = CommandType.Text
End Sub
</code>
<code lang="C#">
public void CreateMySqlCommand()
{
MySqlCommand myCommand = new MySqlCommand();
myCommand.CommandType = CommandType.Text;
}
</code>
</example>
</CommandType>
<Connection>
<summary>
Gets or sets the <see cref="MySqlConnection"/> used by this instance of the
<see cref="MySqlCommand"/>.
</summary>
<value>
The connection to a data source. The default value is a null reference
(<B>Nothing</B> in Visual Basic).
</value>
<remarks>
<para>
If you set <B>Connection</B> while a transaction is in progress and the
<see cref="Transaction"/> property is not null, an <see cref="InvalidOperationException"/>
is generated. If the <B>Transaction</B> property is not null and the transaction
has already been committed or rolled back, <B>Transaction</B> is set to
null.
</para>
</remarks>
<example>
The following example creates a <see cref="MySqlCommand"/> and sets some of its properties.
<code lang="vbnet">
Public Sub CreateMySqlCommand()
Dim mySelectQuery As String = "SELECT * FROM mytable ORDER BY id"
Dim myConnectString As String = "Persist Security Info=False;database=test;server=myServer"
Dim myCommand As New MySqlCommand(mySelectQuery)
myCommand.Connection = New MySqlConnection(myConnectString)
myCommand.CommandType = CommandType.Text
End Sub
</code>
<code lang="C#">
public void CreateMySqlCommand()
{
string mySelectQuery = "SELECT * FROM mytable ORDER BY id";
string myConnectString = "Persist Security Info=False;database=test;server=myServer";
MySqlCommand myCommand = new MySqlCommand(mySelectQuery);
myCommand.Connection = new MySqlConnection(myConnectString);
myCommand.CommandType = CommandType.Text;
}
</code>
</example>
</Connection>
<IsPrepared>
</IsPrepared>
<LastInsertedId>
<summary>Provides the id of the last inserted row.</summary>
<value>
Id of the last inserted row. -1 if none exists.
</value>
<remarks>
An important point to remember is that this property can be used
in batch SQL scenarios but it's important to remember that it will
only reflect the insert id from the last insert statement in the batch.
This property can also be used when the batch includes select statements
and ExecuteReader is used. This property can be consulted during result set
processing.
</remarks>
</LastInsertedId>
<Parameters>
<summary>
Get the <see cref="MySqlParameterCollection"/>
</summary>
<value>
The parameters of the SQL statement or stored procedure. The default is
an empty collection.
</value>
<remarks>
Connector/Net does not support unnamed parameters. Every parameter added to the collection must
have an associated name.
</remarks>
<example>
The following example creates a <see cref="MySqlCommand"/> and displays its parameters.
To accomplish this, the method is passed a <see cref="MySqlConnection"/>, a query string
that is a SQL SELECT statement, and an array of <see cref="MySqlParameter"/> objects.
<code lang="vbnet">
Public Sub CreateMySqlCommand(myConnection As MySqlConnection, _
mySelectQuery As String, myParamArray() As MySqlParameter)
Dim myCommand As New MySqlCommand(mySelectQuery, myConnection)
myCommand.CommandText = "SELECT id, name FROM mytable WHERE age=@age"
myCommand.UpdatedRowSource = UpdateRowSource.Both
myCommand.Parameters.Add(myParamArray)
Dim j As Integer
For j = 0 To myCommand.Parameters.Count - 1
myCommand.Parameters.Add(myParamArray(j))
Next j
Dim myMessage As String = ""
Dim i As Integer
For i = 0 To myCommand.Parameters.Count - 1
myMessage += myCommand.Parameters(i).ToString() &amp; ControlChars.Cr
Next i
Console.WriteLine(myMessage)
End Sub
</code>
<code lang="C#">
public void CreateMySqlCommand(MySqlConnection myConnection, string mySelectQuery,
MySqlParameter[] myParamArray)
{
MySqlCommand myCommand = new MySqlCommand(mySelectQuery, myConnection);
myCommand.CommandText = "SELECT id, name FROM mytable WHERE age=@age";
myCommand.Parameters.Add(myParamArray);
for (int j=0; j&lt;myParamArray.Length; j++)
{
myCommand.Parameters.Add(myParamArray[j]) ;
}
string myMessage = "";
for (int i = 0; i &lt; myCommand.Parameters.Count; i++)
{
myMessage += myCommand.Parameters[i].ToString() + "\n";
}
MessageBox.Show(myMessage);
}
</code>
</example>
</Parameters>
<Transaction>
<summary>
Gets or sets the <see cref="MySqlTransaction"/> within which the <see cref="MySqlCommand"/> executes.
</summary>
<value>
The <see cref="MySqlTransaction"/>. The default value is a null reference (<B>Nothing</B> in Visual Basic).
</value>
<remarks>
You cannot set the <B>Transaction</B> property if it is already set to a
specific value, and the command is in the process of executing. If you set the
transaction property to a <see cref="MySqlTransaction"/> object that is not connected
to the same <see cref="MySqlConnection"/> as the <see cref="MySqlCommand"/> object,
an exception will be thrown the next time you attempt to execute a statement.
</remarks>
</Transaction>
<UpdatedRowSource>
<summary>
Gets or sets how command results are applied to the <see cref="DataRow"/>
when used by the <see cref="System.Data.Common.DbDataAdapter.Update"/> method
of the <see cref="System.Data.Common.DbDataAdapter"/>.
</summary>
<value>
One of the <see cref="UpdateRowSource"/> values.
</value>
<remarks>
<para>
The default <see cref="System.Data.UpdateRowSource"/> value is
<B>Both</B> unless the command is automatically generated (as in the case of the
<see cref="MySqlCommandBuilder"/>), in which case the default is <B>None</B>.
</para>
</remarks>
</UpdatedRowSource>
</docs>