Max (SQL-Server)
I have a table that looks like this:
BARCODE | PRICE | STARTDATE
007023819815 | 159000 | 2008-11-17 00:00:00.000
007023819815 | 319000 | 2009-02-01 00:00:00.000
How ca开发者_如何学Cn I select so I can get the result like this:
BARCODE | PRICE | STARTDATE
007023819815 | 319000 | 2009-02-01 00:00:00.000
select by using max date.
Thanks in advance.
SELECT TOP 1 barcode, price, startdate
FROM TableName
ORDER BY startdate DESC
Or if there can be more than one rows.
SELECT barcode, price, startdate
FROM TableName A
WHERE startdate = (SELECT max(startdate) FROM TableName B WHERE B.barcode = A.barcode)
UPDATE changed second query to view max values per barcode.
An elegant way to do that is using the analytic function row_number
:
SELECT barcode, price, startdate
FROM (
SELECT *
, ROW_NUMBER() OVER (PARTITION BY barcode ORDER BY startdate DESC) as rn
FROM YourTable
) subquery
WHERE rn = 1
If performance is an issue, check out some more complex options in this blog post.
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