Is there a way to loop through a field in all records to check it it's flaged?

Here's what I am wanting to do. I want to be able to flag a certain item as preferred. When I go to flag this item I want it to first check that there is not a product of this type already flaged. I have hundered of products and I am afraid that it will strain the system, but it would be worse if 2 of the same items were flaged preferred.

my product is Product::SKU

So I would want to loop through all the Product::SKU that are identical to the one that I am entering.

something like this.....

loop-----

if(Entered::SKU = Product::SKU and Product::Flag = 1)

"Product already flaged, would you like to change it?")

else

Product::flag = 1

end if

Not sure how to loop it so it reads all the Product::SKU's in exsistance.

One approach would be:

Set field ( globalSKU ; Entered::SKU )

New window ("temp find")

#

Enter Find Mode

Set field (Product::Flag ; 1)

Set field (Product::SKU ; globalSKU)

Set error capture ON

Perform Find

#

If(Get ( FoundCount ) > 0 )

. Show custom dialog ( "change it...?" )

. If ( Get ( LastMessageChoice ) = 2 )

# default button 1 is YES, button 2 is NO

. . Close window ("temp find")

. . Exit Script

. Else

. . Set field (Product::Flag ; "" )

. End If

End If

#

Close window ("temp find")

Set field (Product::Flag ; 1)

I'm not the expert on this, but... look into creating a self-join in the relationship diagram based on the field in question. Then, you can quickly determine whether there is a record on the other side of the link--without scripting, or with minimal scripting, as the case might be.

David