Different execute methods of ADO.NET command object are Execute Scalar() , Execute reader() , ExecuteNonQuery(). ExecuteScalar() fetches only a single object. ExecuteReader() fetches result set with multiple rows and loads to datareader. ExecuteNonquery() executes sql statements for insert,update and delete.

*C# ExecuteNonQuery *C# ExecuteReader *C# ExecuteScalar

ExecuteScalar:- This method returns a single value from the first row and first column of the result get from the execution of SQL query. ExecuteNonQuery:- This method executes the DML SQL query just like insert, delete or update and then returns the number of rows affected by the action. ExecuteReader:- This method returns DataReader object which is a forward-only resultset. ExecuteXMLReader:- This method is available for SQL Server 2000 or later. Upon execution it builds XMLReader object from standard SQL query.