Re: how to suppress similar rows while copying from one table to another?

[Daniel John Debrunner]

Rick Hillegas wrote:

One way to solve this problem would be to put a filtering function in 
the WHERE clause of the driving SELECT statement. Something like this:

INSERT INTO targetTable
SELECT * FROM sourceTable
WHERE isFirstInstance( tastyColumn1, tastyColumn2 ) = 1

Here isFirstInstance is a function which returns 1 the first time it 
sees a given key combination and returns 0 on all subsequent sightings. 
You, of course, have to write this user function.

Any thoughts on how to do that? Since such calls are stateless how would 
you identify it's the first call for a query execution?

Dan.