The Fill method of the DataAdapter is used to populate a DataSet with the results of the SelectCommand of the DataAdapter . Fill takes as its arguments a DataSet to be populated, and a DataTable object, or the name of the DataTable to be filled with the rows returned from the SelectCommand .
Is DataReader faster than DataSet?
DataReader is a stream which is readonly and forward only. DataReader releasese the records as query executes and do not wait for the entire query to execute. Therefore it is very fast as compare to the dataset. It releases only when read method is called.
What is data table and how fill data in data table using DataReader?
You can load a DataTable directly from a data reader using the Load() method that accepts an IDataReader . You don’t even need to define the columns. Just create the DataTable and Fill it. Here, cString is your connection string and sql is the stored procedure command.
What is da fill DT?
Fill(DataSet) Adds or refreshes rows in the DataSet to match those in the data source. Fill(DataTable, IDataReader) Adds or refreshes rows in the DataTable to match those in the data source using the DataTable name and the specified IDataReader.
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. If you want random access and do not need to worry about having a constant connection with the database, go with DataSet.
What is DataSet and DataReader?
Dataset is used to hold tables with data. DataReader is designed to retrieve a read-only, forward-only stream of data from data sources. DataReader has a connection oriented nature, whenever you want fetch the data from database that you must have a connection.
What is the difference between DataReader and DataSet?
How to populate DataTable and dataset with data from DataReader?
The DataTable and DataSet will be populated with records from the DataReader using Load method of the DataTable. I have made use of the following table Customers with the schema as follows.
How to copy records from a DataReader to a dataset?
The following screenshot displays the DataTable with records copied from the DataReader. The records from the Customers table are fetched using SqlDataReader. Then a new DataSet is created and a DataTable is added to the DataSet. Finally the DataReader records are loaded into the DataTable of the DataSet using its Load method.
How to add rows/columns to a DataReader dataset?
you would simply add the rows/columns appropriately into the dataset when you are reading from the DataReader. There is an easier way, which everything is done for you. Use the SqlDataAdapter to fill your dataset with the select command.
How can I return a dataset instead of a sqldatareader?
Instead of returning a SqlDataReader, you can change your code so that it returns a DataSet. One of the neat things about this approach is that Fill opens and closes the database connection for you. If your SelectCommand is stored procedure, the Fill method of the adapter will rise exception.
