Comments on: How to find the max row per group in SQL without subqueries http://www.xaprb.com/blog/2007/03/14/how-to-find-the-max-row-per-group-in-sql-without-subqueries/ Stay curious! Tue, 06 Jan 2009 10:29:42 +0000 http://wordpress.org/?v=2.6.2 By: Find a First/Last Row of Data Without Sub-Queries | JB and Me http://www.xaprb.com/blog/2007/03/14/how-to-find-the-max-row-per-group-in-sql-without-subqueries/#comment-15257 Find a First/Last Row of Data Without Sub-Queries | JB and Me Sat, 18 Oct 2008 23:45:04 +0000 http://www.xaprb.com/blog/?p=307#comment-15257 [...] but effective–just follow the guidelines in this post. Performance is great, much better by far than using sub-queries. I found a marginal performance [...] [...] but effective–just follow the guidelines in this post. Performance is great, much better by far than using sub-queries. I found a marginal performance [...]

]]> By: RobertPhoenix http://www.xaprb.com/blog/2007/03/14/how-to-find-the-max-row-per-group-in-sql-without-subqueries/#comment-14925 RobertPhoenix Sat, 02 Aug 2008 00:04:03 +0000 http://www.xaprb.com/blog/?p=307#comment-14925 This looks good when you only have one person of minimum age for each genger. If you add another row, say 5 robert m You will get three rows in the result, which may not be what was wanted. This looks good when you only have one person of minimum age for each genger. If you add another row, say

5 robert m

You will get three rows in the result, which may not be what was wanted.

]]> By: Xaprb http://www.xaprb.com/blog/2007/03/14/how-to-find-the-max-row-per-group-in-sql-without-subqueries/#comment-5055 Xaprb Sat, 17 Mar 2007 12:18:09 +0000 http://www.xaprb.com/blog/?p=307#comment-5055 <p>Aaron, that query is possible in some RDBMSs (notably MySQL with strict mode disabled) but it's a <a href="/blog/2006/03/11/many-to-one-problems-in-sql/">many-to-one trap</a>.</p> Aaron, that query is possible in some RDBMSs (notably MySQL with strict mode disabled) but it’s a many-to-one trap.

]]> By: Aaron http://www.xaprb.com/blog/2007/03/14/how-to-find-the-max-row-per-group-in-sql-without-subqueries/#comment-5036 Aaron Fri, 16 Mar 2007 18:42:28 +0000 http://www.xaprb.com/blog/?p=307#comment-5036 <p>Can't you do <code>select *,min(age) from person group by gender</code>? Maybe not.</p> Can’t you do
select *,min(age) from person group by gender? Maybe not.

]]> By: Anonymous http://www.xaprb.com/blog/2007/03/14/how-to-find-the-max-row-per-group-in-sql-without-subqueries/#comment-5000 Anonymous Thu, 15 Mar 2007 16:47:03 +0000 http://www.xaprb.com/blog/?p=307#comment-5000 <p>If you only need to see min/max values and the group, then <code>select gender,min(age) from person group by gender</code> will work for you too.</p> If you only need to see min/max values and the group, then

select gender,min(age) from person group by gender

will work for you too.

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