Dataset and dataadapter

Dataset is an object in memory, and dataadapter is related to database connection information.

Therefore, to update a dataset in batches, you must use dataadapter.

Static PrivateDataset createcommandandupdate ( StringConnectionstring, StringQuerystring) { Dataset dataset =NewDataset ();   Using(Oledbconnection connection = NewOledbconnection (connectionstring )) { Connection. open (); Oledbdataadapter adapter = NewOledbdataadapter (); Adapter. selectcommand = NewOledbcommand (querystring, connection ); Oledbcommandbuilder builder = NewOledbcommandbuilder (adapter );   Adapter. Fill (Dataset );   // Code to modify data in the dataset here.   // Without the oledbcommandbuilder, this line wowould fail. Adapter. updatecommand = builder. getupdatecommand (); Adapter. Update (Dataset ); } ReturnDataset; }

This mechanism also brings about a benefit. For example, if we want to retrieve data from a database and update it to another database, we can use dataset as an intermediate carrier.