Ok. I did not have example like this (I put it as easy to understand example) but I was curious. Is this kind of clause makes any difference? I made my test database with tables with same fields as in my example. I made relation between tables. I filled orders table with 10000 records and partners table with 1000 records. Than I made query same as in my example and received 10000 reads from orders and 10000 reads from partners where orders were Non-index reads and partner were Index reads. Than I try this Join cluse and guess what? I received EXACTLY THE SAME PERFOMANCE ANALYSIS.
Maybe it is something wrong with JOIN clause or maybe I am right... Regards, Djole From: mailto:[email protected] Sent: Friday, September 09, 2016 3:01 PM To: [email protected] Subject: [firebird-support] Re: Optimizer request In is slow. Better to optimize the query like this: Select o.* >From orders o Inner join ( Select p.Partid From Partners p Where p.country = SPAIN }as partidentity On partidentity.Partid = o.PartID Which should be faster than a straight join i.e Select o.* from orders o inner join partners p on p.Partid = o.partid Where p.country = SPAIN Jez
