Question

I have a table that records a sequence of actions with a field that records the sequence order:

user    data    sequence 1       foo     0 1       bar     1 1       baz     2 2       foo     0 3       bar     0 3       foo     1 

Selecting the first item for each user is easy enough with WHERE sequence = ‘0’ but is there a way to select the last item for each user in SQL?

The result I am after should look like this:

user    data    sequence 1       baz     2 2       foo     0 3       foo     1 

I’m using MySQL if there are any implementation specific tricksters answering.

Answer 1

This sql will return the record with the highest sequence value for each user:

select a.user, a.data, a.sequence from table as a     inner join (         select user, max(sequence) as 'last'         from table          group by user) as b     on a.user = b.user and         a.sequence = b.last