Simplify ticker's 'last' query.  We know AUD are a_type and BTC are b_type, so we don't need the two JOINs.
Simplify ticker's 'last' query.  We know AUD are a_type and BTC are b_type, so we don't need the two JOINs.

dooglus/intersango,dooglus/intersango,bankonme/intersango,bankonme/intersango,dooglus/intersango,dooglus/intersango,bankonme/intersango,bankonme/intersango