On Fri, Feb 29, 2008 at 3:55 PM, Martijn van Oosterhout <kleptog@xxxxxxxxx> wrote:
Quickly for sure... but I don't think 'without processing all the rows that qualify'. I think it will still process all the rows and return just one.
Best regards,On Fri, Feb 29, 2008 at 02:53:05PM +0530, Gurjeet Singh wrote:Except if you have an index on the column you're ordering by. Then the
> In my opinion (without looking at the code), if you have a grouping-function
> or ORDER BY or GROUP BY clause, then yes, the whole query has to be executed
> to show the first row of the result-set. But if the query doesn't have any
> of these clauses, then the DB has the ability to send back the first row
> from the result as soon as it processes it (i.e after WHERE clause
> processing), and stop the query execution there.
server can really return the first row quickly.
Quickly for sure... but I don't think 'without processing all the rows that qualify'. I think it will still process all the rows and return just one.
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