Re: Please help me write a query

On 5/27/2010 9:04 AM, Nikolas Everett wrote:
> Say I have a table that stores state transitions over time like so:
> id, transitionable_id, state1, state2, timestamp
>
> I'm trying to write a query that coalesces changes in state2 away to
> produce just a list of transitions of state1. I guess it would look
> something like
>
> SELECT state1, FIRST(timestamp)
> FROM table
>
> but I have no idea how to aggregate just the repeated state1 rows.

if i understand what your after

Select distinct transitinable_id, state1, min(timestamp) from table
group by transitinable_id, state1

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