请帮我解读这篇代码（是关于vb与access的连接）

Dim db As Connection
  Set db = New Connection
  db.CursorLocation = adUseClient
  db.Open "PROVIDER=Microsoft.Jet.OLEDB.4.0;Data Source=C:\1.MDB;"                '建立连接
  Set RS = New Recordset
  RS.Open "select * from aaa", db, adOpenStatic, adLockOptimistic                  '打开记录集
'==============读出所有记录==============
  rs.MoveFirst
  Do While Not rs.EOF
  Print rs("aa"), rs("bb"), rs("cc")
  rs.MoveNext
  Loop

'==============读出bb列的所有内容========
rs.MoveFirst
Do While Not rs.EOF
  Print rs("bb")
  rs.MoveNext
  Loop

'==============添加新记录===========
rs.AddNew
rs("aa") = "a4"
rs("bb") = "b4"
rs("cc") = "c4"
rs.Update
'==============更改一条记录========
rs.MoveFirst
Do While Not rs.EOF
  If rs("aa") = "a2" Then
  rs("aa") = "a22"
  rs("bb") = "b22"
  rs("cc") = "c22"
  rs.Update
  Exit Do
  else
&nb