NYCPHP Meetup

[Dan Cech]

Ben Sgro wrote:
> I have a table that includes an id (not unique and a version).
> 
> A unique row is identified by both the id and version. This is for MSSQL.
> 
> I want to select all the id's, but only return the most up to date version.
> 
> So, for a table
> 
> id | version
> -------------
> 1 | 0
> 1 | 1
> 2 | 0
> 2 | 1
> 2 | 2
> 
> The query should return
> 
> id | version
> -------------
> 1 | 1
> 2 | 2
> 
> Any help much appreciated.

This problem is sometimes referred to as the group-wise maximum.  I'm 
not sure if they would work in mssql but there are a couple of potential 
solutions for mysql outlined here:

http://dev.mysql.com/doc/refman/4.1/en/example-maximum-column-group-row.html

Dan