Design Patterns discussion

[Zhai <myzhai AT yahoo.com.cn>]

In a software system, we meet the following
requirements:
  a client program, when running, have to set or get a
parameter, named paraValue.
But the parameter paraValue could be stored in a file
named filePara, or in a relation
database, such as Oracle. Now we design an abstract
class "CParaAccess", with two
public virtual functions setPara() and getPara() to
set and get the parameter.
There are two subclasses "CFileParaAccess" and
"CDatabaseParaAccess" inherited
 from "CParaAccess", all implement setPara() and
getPara(). However in 
 "CFileParaAccess" and "CDatabaseParaAccess", the
principle to implement
 setPara() and getPara() is different. 
   In the design we can understand the client had two
strategies to set/get the 
 parameter, i.e. from a file or a database. so can we
think our design cohere 
 with the Strategy design pattern? If not, which
pattern could we use to improve
 the design?
 thx.

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