Composition
--Data set (in-memory database)
--dataset Data Set
--datatable Data Sheet
--datacolumn Data Columns
--datarow Data rows
--dataview Data View
--net Data Provider
--connection Connection (bridge between program and database)
--open/close
--connectionstring: Connection string (information for the target database)
--Server: Server/data source
--User name: Uid/user ID
--Password: Pwd/password
--Database: Database/initial Catalog
--command command (Perform action)
--connection: Connect
--commandtype: Command Type (text/storedprocedure)
--commandtext: Command text (SQL statement/stored procedure name)
--executenonquery: Performs an action that returns the number of rows affected
--executereader: Execute query, return DataReader
--executescalar: Executes the query and returns the first column of the first row
--datareader Reader (read-only, forward-only, read-only)
--read () 1) forward to next 2) return bool
--dataadapter Adapter (bridge between dataset and database)
--fill: Populating (Populating database data into datasets)
--update: Update (update data from DataSet to database)