How about with par_ as (select * from product_parent where parent_name like 'aa%' ) select distinct product_code from product p_ inner join par_ on p_.parent_id=par_.id limit 2
? 2012/4/3 Istvan Endredy <istvan.endr...@gmail.com> > Hi, > > i've ran into a planning problem. > > > select distinct product_code from product p_ > inner join product_parent par_ on p_.parent_id=par_.id > where par_.parent_name like 'aa%' limit 2 > > > If effective_cache_size is smaller (32MB), planning is ok and query is > fast. (10ms) > In the worst case (effective_cache_size=6GB) the speed depends on the > value of 'limit' (in select): if it is smaller, query is slower. (12ms) > > > -- Best regards, Vitalii Tymchyshyn
