Create Multiple Records on Import

[ScrewBalll]

Hi there, I'm in dire need of some help regarding an import that I am carrying out.
The general idea is that I'm importing a price and a validity period into a table (pricing condition). If the validity period falls within another period then I want several records inputted to explain the behaviour.

Its probably best if I show you an example:

Data already in the table:
[Price1] [Price2] [ValidFrom] [ValidTo]
0 10 01/01/05 31/12/05

Incoming Data:-
[Price1] [Price2] [ValidFrom] [ValidTo]
20 0 01/02/05 15/02/05

I want this to map to:
[Price1] [Price2] [ValidFrom] [ValidTo]
0 £10 01/01/05 31/01/05
£20 £10 01/02/05 15/02/05
0 £10 16/02/05 31/12/05

You see how the dates have been updated and importing 1 record has update one record and created 2 more. This is a very simple example (for 1 item) but gives the basic idea (There will also be records in the database and multiple items coming in). I will be importing in the region of 10000 records and don't really want to think about using a cursor to filter through all the results.

If anyone has any ideas please help.