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Re: Need help for constructing query

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On 2011-03-27 rsmogura@xxxxxxxxxxxxxxx (RadosÅaw Smogura) wrote:

> Marco <netuse@xxxxxxxxxxx> Friday 25 March 2011 14:25:47
> > Hi,
> > 
> > I have a table like this:
> > 
> > id	date		min	max	value
> > 1	2011-03-25	20	30	17
> > 3	2011-03-21	40	55	43
> > 3	2011-03-23	40	55	52
> > 2	2011-02-25	5		2
> > 4	2011-03-15			74
> > 4	2011-03-25			128
> > 1	2011-03-22	20	30	24
> > 
> > I'm looking for a query that outputs the last rows (highest date) per id
> > where the value is between min and max. I already have problems displaying
> > the last rows per id. Something like
> > 
> > select id, max(date) from mytable group by id;
> > 
> > gives just the id and the date, not the other values. I think of doing
> > this in two steps:
> > 
> > 1) Display the rows with the highest date per id. That gives as many rows
> > as ids exist.
> > 2) Remove the rows that do not match ( value<max and value>min )
> > 
> > 
> > Marco
> SELECT * FROM where (min < value and value < max) and (id, date) in (
> 	SELECT id, max(date) WHERE (min < value and value < max) group by
> id)

This seems to do the task. Thanks you for the snippet!


Marco


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