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From Daniel John Debrunner <...@apache.org>
Subject Re: how to suppress similar rows while copying from one table to another?
Date Fri, 16 Nov 2007 17:35:48 GMT
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?


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