Which is a DataReader method?
A DataReader parses a Tabular Data Stream from Microsoft SQL Server, and other methods of retrieving data from other sources. A DataReader is usually accompanied by a Command object that contains the query, optionally any parameters, and the connection object to run the query on.
What is GetOrdinal C#?
GetOrdinal is kana-width insensitive. Because ordinal-based lookups are more efficient than named lookups, it is inefficient to call GetOrdinal within a loop. Save time by calling GetOrdinal one time and assigning the results to an integer variable for use within the loop.
Do I need to close DataReader?
You must ensure the Close method is called when you are through using the SqlDataReader before using the associated SqlConnection for any other purpose. The Close method may either be called directly or through the Dispose method, disposing directly or in the context of the using statement block.
What is the difference between DataReader and DataAdapter?
Key differences in simple terms: DataAdapter is an intermediate layer/ middleware which acts a bridge between the DataSet and a Database whereas DataReader provides forward-only, read-only access to data using a server-side cursor (simply put it is ued to read the data).
What is column ordinal?
column ordinal [the ~] noun – A number that represents the position of the column in a set of columns. So, if a table has 3 columns, named Name, Address, and Zip, in that order, their ordinals are 0, 1, and 2. the column ordinal. – A number that represents the position of the column in a set of columns.
Which is the correct way to declare a DataReader?
After creating an instance of the Command object, you create a DataReader by calling Command. ExecuteReader to retrieve rows from a data source, as shown in the following example. SqlDataReader myReader = myCommand. ExecuteReader();…ADO.NET DataReader
- SqlDataReader.
- OleDbDataReader.
- OdbcDataReader.
Is it necessary to manually close and DIspose of SqlDataReader?
You don’t need the . Close() statement in either sample: it’s handled by the . Dispose() call.
What’s better DataSet or DataReader?
DataReader provides faster performance, but has read-only and forward-only access. DataSet, on the other hand, is high resource-consuming, but offers more control and a disconnected nature.
Why is DataReader forward-only?
In other words, a DataReader is a stream of data that is returned from a database query. It reads only one row at a time from the database and can only move forward. This helps application performance since only one row of data is stored at a time. However, the DataReader cannot edit data while traversing over it.