Re: [HACKERS] Cache query (PREPARE/EXECUTE)

On Tue, 22 Feb 2000, Tom Lane wrote:

> Karel Zak - Zakkr <zakkr@zf.jcu.cz> writes:
> >  as I said, I tring implement PREPARE / EXECUTE command for user a
> > controllable query cache (in TODO: Cache most recent query plan(s)).
> 
> Looks cool.

Thanks.

> 
> > The queryTree and planTree are save in hash table and in the 
> > TopMemoryContext (Is it good space for this cache?).
> 
> Probably not.  I'd suggest making a separate memory context for
> this purpose --- they're cheap, and that gives you more control.
> Look at the creation and use of CacheMemoryContext for an example.

 Yes, I agree (TopMemoryContext was simpl for first hacking). 
But I not sure how create new (across transaction persistent?) 
MemoryContext. It needs new portal? (Sorry I not thoroughly explore
PG's memory management.)  

> 
> > I'am not sure with syntax, now is:
> 
> >         PREPARE name AS optimizable-statement [ USING type, ... ]
> >         EXECUTE name [ USING value, ... ] 	
> 
> > Comments? Suggestions? (SQL92?)
> 
> This seems to be quite at variance with SQL92, unfortunately, so it
> might not be a good idea to use the same keywords they do...

 Hmm, I inspire with Jan's TODO item. What use:

	CREATE PLAN 
	DROP PLAN
	EXECUTE PLAN

 IMHO these kaywords are better.
						Karel