The most commonly used methods of the DataAdapter are:
Fill:
This method executes the SelectCommand to fill the DataSet object with data from the data source.
Depending on whether there is a primary key in the DataSet, the ‘fill’ can also be used to update an existing table in a DataSet with changes made to the data in the original datasource.
FillSchema
This method executes the SelectCommand to extract the schema of a table from the data source.
It creates an empty table in the DataSet object with all the corresponding constraints.
Update
This method executes the InsertCommand, UpdateCommand, or DeleteCommand to update the original data source with the changes made to the content of the DataSet.
Some basic methods of dataadpater are:
a. Fill: adds or updates the rows to dataset from the datasource
b. FillSchema: adds a datatable with the sameschema as in the datasource
c. Update: it calls insert, update, delete sql commands for transferring all the changes from the dataset to the datasource
d. Dispose : releases all the resources