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From Guy Rouillier <guyr-...@burntmail.com>
Subject Re: Select one set null instead of throwing exception
Date Mon, 05 Oct 2009 06:07:20 GMT
Ignore this.  I realized after taking a break that it doesn't work with 
primitive types.  I think the thing I find most frustrating with Java is 
that it doesn't treat primitive types in a consistent manner with 
classes derived from Object.

Guy Rouillier wrote:
> Currently, performing a single row select throws an exception if zero or 
>  > 1 rows are returned.  While this is certainly workable, an 
> alternative that would be easier on the programmer would be to set the 
> result to null if no rows are found, and only throw an exception if > 1 
> rows are found.
> 
> The documentation suggests doing a count to determine what situation you 
> are in, then issuing the appropriate select once you know.  But that 
> will result in an extra trip to the DB.  In a common scenario where you 
> are querying a primary key, you know that you will get zero or one row 
> back.  So rather than having to put the single row select into a 
> try-catch block, a more natural paradigm would be to assign the result 
> and then check the result for null.
> 


-- 
Guy Rouillier

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