Hi All,
Takeshi Yamamuro gave some comments on this topic on twitter. And after
more research, here are correction and updates of my understanding about
bottom-up and top-down now.
Bottom-up and top-down are just 2 strategies to enumerate join order and
generate the search space. Both of them can
Hi, Xiaoju,
Thanks for sending this to the dev list. The current join reordering rule
is just a stats based optimizer rule. Either top-down or bottom-up
optimization can achieve the same-level optimized plans. DB2 is using
bottom up. In the future, we plan to move the stats based join reordering
r
