When should I use DataReader and DataAdapter?
DataReader requires an open connection in order to execute the SQL statement. Example would be fetching Name City for all records in the Person Table using DataReader. DataAdapter is used to execute SQL statements and is used to populate the results of SQL Query into a DataSet or DataTable.
What is connection commands DataReader and DataAdapter?
Using the DataReader can increase application performance both by retrieving data as soon as it is available, and (by default) storing only one row at a time in memory, reducing system overhead. A DataAdapter is used to retrieve data from a data source and populate tables within a DataSet.
What is the difference between DataReader and DataSet object?
Dataset or DataReader? The DataSet class in ADO.Net operates in an entirely disconnected nature, while DataReader is a connection oriented service. DataSet is an in-memory representation of a collection of Database objects including related tables, constraints, and relationships among the tables.
What is the purpose of DataAdapter?
The DataAdapter serves as a bridge between a DataSet and a data source for retrieving and saving data. The DataAdapter provides this bridge by mapping Fill, which changes the data in the DataSet to match the data in the data source, and Update, which changes the data in the data source to match the data in the DataSet.
What is the difference between a DataTable and a DataReader?
Using a DataReader, you can access each column of the result set, read all rows of the set, and advance to the next result set if there are more than one. DataTable represents a single table in the database. It has rows and columns.
Can we use DataReader in Web services?
Can we use data reader object in webservices? Yes, we can use the data reader object in web services. This is because web services include business logic therefore we can use this object to read data values from the database.
What is SQL DataReader?
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 DataAdapter in VB net?
What is the use of DataReader?
The DataReader provides an unbuffered stream of data that allows procedural logic to efficiently process results from a data source sequentially. The DataReader is a good choice when you’re retrieving large amounts of data because the data is not cached in memory.
How can we load multiple tables in a DataSet?
Filling a DataSet with multiple tables can be done by sending multiple requests to the database, or in a faster way: Multiple SELECT statements can be sent to the database server in a single request. The problem here is that the tables generated from the queries have automatic names Table and Table1.