converting the following sql

Outcome.find(:all, :conditions => 'outcomes.outcome_date = (select
max(o2.outcome_date) from outcomes o2 where o2.testrun_id =
outcomes.testrun_id and o2.testcase_id = outcomes.testcase_id)')

Thanks.

BUt im still struggling, for example, theres a slight change:

select count(*) from outcomes o1 where o1.outcome_date = (select
max(o2.outcome_date) from outcomes o2 where o2.testrun_id =
o1.testrun_id and o2.testcase_id = o1.testcase_id and o1.testrun_id =
'31' and o1.result_id = '1');

I want to substitute the '31' with instance variable @testrun

so in your example, how do i escape the '' string to insert the instance
variable:

GUESS in CAPS:

...
....
o2.testcase_id = outcomes.testcase_id AND {OUTCOMES.TESTRUN_ID =>
@TESTRUN} and outcomes.result_id = "1")')

thanks though, i now understand alot more!

Building on Maurício's response:

Outcome.find(:all, :conditions => ['outcomes.outcome_date = (SELECT
MAX(o2.outcome_date) FROM outcomes AS o2 WHERE o2.testrun_id =
outcomes.testrun_id AND o2.testcase_id = outcomes.testcase_id)
AND outcomes.testrun_id = ? AND outcomes.result_id = ?',
@testrun, '1'])

You were close. Look at the docs for the conditions value, the
form of an array is:
  ["sql fragment with placeholders',
   placeholder_1_value, placeholder_2_value]

-Rob

Rob Biedenharn http://agileconsultingllc.com
Rob@AgileConsultingLLC.com