On Sun, Dec 26, 2021, at 23:25, Corey Huinker wrote: > My second guess would be: > FROM permission p > LEFT JOIN role AS r ON [FOREIGN] KEY [(p.col1 [, p.col2 ...])] > > where the key spec is only required when there are multiple foreign keys in > permission pointing to role. > > But my first guess would be that the standards group won't get around to it.
It's a quite nice idea. It would definitively mean an improvement, compared to today's SQL. Benefits: * Ability to assert the join is actually performed on foreign key columns. * Conciser thanks to not always having to specify all key columns on both sides. However, I see one problem with leaving out the key columns: First, there is only one FK in permission pointing to role, and we write a query leaving out the key columns. Then, another different FK in permission pointing to role is later added, and our old query is suddenly in trouble. /Joel
