将 CommandText 发送给 Connection,并使用某个 CommandBehavior 值来构建 DB2DataReader。
[Visual Basic]
Public Function ExecuteReader( _
ByVal behavior As CommandBehavior _
) As DB2DataReader
[C#]
public DB2DataReader
ExecuteReader(
CommandBehavior behavior
);
[C++]
public: DB2DataReader
* ExecuteReader(
CommandBehavior behavior
);
[JScript]
public function ExecuteReader(
behavior : CommandBehavior
) : DB2DataReader
;
DB2DataReader 实例。
如果期望 SQL 语句仅返回单行,那么将 SingleRow 指定为 CommandBehavior 值可提高应用程序性能。
DB2DataReader 支持特殊方式,此方式实现了大二进制值的有效读取。有关更多信息,请参阅 CommandBehavior 的 SequentialAccess 设置。
可以同时访问使用同一个 DB2Connection 实例的多个 DB2DataReader 实例中的数据。每个 DB2DataReader 实例都必须与它自己的 DB2Command 实例相关联。
[Visual Basic, C#] 以下示例将创建 DB2Command,然后通过传递作为 SQL SELECT 语句的字符串和用来连接数据库的字符串来执行该命令。随后将 CommandBehavior 设置为 CloseConnection。
[Visual Basic]
Public Sub CreateMyDB2DataReader(mySelectQuery As String, _
myConnectionString As String)
Dim myConnection As New DB2Connection(myConnectionString)
Dim myCommand As New DB2Command(mySelectQuery, myConnection)
myCommand.Connection.Open()
Dim myReader As DB2DataReader =
myCommand.ExecuteReader(CommandBehavior.CloseConnection)
While myReader.Read()
Console.WriteLine(myReader.GetString(0))
End While
myReader.Close()
myConnection.Close()
End Sub
[C#]
public void CreateMyDB2DataReader(string mySelectQuery,string myConnectionString)
{
DB2Connection myConnection = new DB2Connection(myConnectionString);
DB2Command myCommand = new DB2Command(mySelectQuery, myConnection);
myCommand.Connection.Open();
DB2DataReader myReader =
myCommand.ExecuteReader(CommandBehavior.CloseConnection);
while(myReader.Read())
{
Console.WriteLine(myReader.GetString(0));
}
myReader.Close();
myConnection.Close();
}