Re: postgres_fdw join pushdown (was Re: Custom/Foreign-Join-APIs)

Hi Ashutosh,

Sorry for leaving the thread.

2015-07-20 16:09 GMT+09:00 Ashutosh Bapat <ashutosh.bapat@enterprisedb.com>:
> In find_user_mapping(), if the first cache search returns a valid tuple, it
> is checked twice for validity, un-necessarily. Instead if the first search
> returns a valid tuple, it should be returned immediately. I see that this
> code was copied from GetUserMapping(), where as well it had the same
> problem.

Oops.  I changed find_user_mapping to exit immediately when any valid
cache was found.

> In build_join_rel(), we check whether user mappings of the two joining
> relations are same. If the user mappings are same, doesn't that imply that
> the foreign server and local user are same too?

Yes, validity of umid is identical to serverid.  We can remove the
check for serverid for some cycles.  One idea is to put Assert for
serverid inside the if-statement block.

> Rest of the patch looks fine.

Thanks