ChrisM@Work (8/28/2013)
John's correct, here's another way:
SELECTcol1 = MIN(CASE WHEN t.value = x.min_value THEN value ELSE NULL END),
col2 = MIN(CASE WHEN t.value = x.min_value THEN t_stamp ELSE NULL END),
col3 = MIN(CASE WHEN t.value = x.max_value THEN value ELSE NULL END),
col4 = MIN(CASE WHEN t.value = x.max_value THEN t_stamp ELSE NULL END)
FROM @t t
CROSS APPLY (
SELECT min_value = MIN(value), max_value = MAX(value)
FROM @t
) x
WHERE t.value IN (x.min_value, x.max_value)
+1 for a bizarre but wonderful query!
It inspired me to come up with this:
SELECT col1 = MIN(CASE WHEN a.t_stamp = mv1 THEN value ELSE NULL END),
col2 = MIN(CASE WHEN a.t_stamp = mv1 THEN t_stamp ELSE NULL END),
col3 = MIN(CASE WHEN a.t_stamp = mv2 THEN value ELSE NULL END),
col4 = MIN(CASE WHEN a.t_stamp = mv2 THEN t_stamp ELSE NULL END)
FROM (
SELECT value, t_stamp
,mv1=MIN(t_stamp) OVER (PARTITION BY (SELECT NULL))
,mv2=MAX(t_stamp) OVER (PARTITION BY (SELECT NULL))
FROM @t) a
WHERE t_stamp = mv1 OR t_stamp = mv2
My thought question: Have you ever been told that your query runs too fast?
My advice:
INDEXing a poor-performing query is like putting sugar on cat food. Yeah, it probably tastes better but are you sure you want to eat it?
The path of least resistance can be a slippery slope. Take care that fixing your fixes of fixes doesn't snowball and end up costing you more than fixing the root cause would have in the first place.
Need to UNPIVOT? Why not CROSS APPLY VALUES instead?[/url]
Since random numbers are too important to be left to chance, let's generate some![/url]
Learn to understand recursive CTEs by example.[/url]
[url url=http://www.sqlservercentral.com/articles/St