Re: Assertion failure from plan cache invalidation

On 13/08/10 18:18, Tom Lane wrote:
> Heikki Linnakangas<heikki.linnakangas@enterprisedb.com>  writes:
>> PushOverrideSearchPath() assumes that if the temporary namespace existed
>> when an override search path was memorized with GetOverrideSearchPath(),
>> it must still exist. That's not true in the above example, rolling back
>> the transaction that the temporary namespace was created in drops it.
>
> Hm ... seems like there are two possibilities here.  We could forcibly
> recreate the temp schema, or we could just ignore the useTemp flag.

Yeah, I was undecided on that too.

> The former would more nearly approximate the situation that prevailed
> at GetOverrideSearchPath() time, but on the other hand it's not clear
> that it's a good idea for PushOverrideSearchPath() to have side-effects
> like that.  I *think* that it'd be safe, at least for the two existing
> callers, but ...
>
> In the plancache case it could be argued that there's no real reason
> to recreate the temp schema: it would necessarily be empty, so it
> couldn't affect the results of planning anyhow.  So the second solution
> would work just fine for the current usage.
>
> Thoughts?

Let's do the latter, add a comment noting that, and extend it later if
necessary.

--
   Heikki Linnakangas
   EnterpriseDB   http://www.enterprisedb.com