How to ADO.NET DataReader
DataReader Object in ADO.NET is a stream-based , forward-only, read-only retrieval of query results from the Data Source, which do not update the data. The DataReader cannot be created directly from code, they created only by calling the ExecuteReader method of a Command Object.
DataReader Object provides a connection oriented data access to the data Sources. A Connection Object can contain only one DataReader at a time and the connection in the DataReader remains open and cannot be used for any other purpose while data is being accessed. When started to read from a DataReader it should always be open and positioned prior to the first record. The Read() method in the DataReader is used to read the rows from DataReader and it always moves forward to a new valid row, if any row exist .
There are two types of DataReader in ADO.NET. They are SqlDataReader and the OleDbDataReader. The System.Data.SqlClient and System.Data.OleDb are containing these DataReaders respectively. From the following link you can see in details about these classes.
- ADO.NET Connection Object
- ADO.NET SQL Server Connection
- ADO.NET OLEDB Connection
- ADO.NET ODBC Connection
- ADO.NET Command
- ADO.NET ExecuteNonQuery in SqlCommand Object
- ADO.NET ExecuteNonQuery in OleDbCommand Object
- ADO.NET ExecuteScalar in SqlCommand Object
- ADO.NET ExecuteScalar in OleDbCommand Object
- ADO.NET ExecuteReader in SqlCommand Object
- ADO.NET ExecuteReader in OleDbCommand Object
- How to ADO.NET SqlDataReader
- How to ADO.NET OleDbDataReader
- How to Multiple Result Sets in ADO.NET
- Getting Schema Informations from SqlDataReader
- Getting Schema Informations from OleDbDataReader
- What is DataAdapter
- What is SqlDataAdapter
- What is OleDbDataAdapter
- Vb.NET ExecuteReader and ExecuteNonQuery