Re: pg_class_aclcheck: relation [oid] not found...

Sean Chittenden <sean@chittenden.org> writes:
> Hrm...  this limitation makes temporary tables that drop on commit +
> pl/pgsql unusable beyond the 1st transaction.  Is there a mechanism to
> test to see if a relation in a plan is a temporary table?  It seems as
> though in pl_exec.c that around 1926 it'd be possible to add a test to
> see if the plan uses temporary tables and add a new member to struct
> expr telling exec_stmt_execsql to free the plan around line 2016 when
> its cleaning up after itself.

That's entirely the wrong way to go about it.  Temp tables are only one
manifestation of a general problem with stale plans.  For instance, if
someone drops an index that your query uses, you've got a problem.

What we need is a general mechanism that keeps track of all the DB
objects that a cached plan depends on (tables, views, functions, yadda
yadda) and invalidates the plan when any of those objects are dropped or
altered.  At the low level, such a mechanism already exists (the
syscache inval stuff) --- the problem is to connect it up to plan
caching.

            regards, tom lane