Thread: explicit joins vs implicit joins

Once upon a time when I taught myself sql I learned the explicit join
syntax-- I have never really used the where clause to create joins.
With this style of sql I have been building/maintaining a
postgresql-centric web application since postgresql 7.0 and now I am
learning that by writing my sql in this fashion I am constricting the
planner. After reading this:

http://marc.theaimsgroup.com/?l=postgresql-general&m=105551123915183&w=2

I am wondering if things are going to change in 7.4?  Or should I switch
to placing joins in the where clause when I can?  I don't want to have
to worry about my join order-- I would prefer to let the planner do its
thing 95% of the time.

culley

On Thu, Jun 19, 2003 at 09:52:26 +0200,
  culley harrelson <culley@fastmail.fm> wrote:
> Once upon a time when I taught myself sql I learned the explicit join
> syntax-- I have never really used the where clause to create joins.
> With this style of sql I have been building/maintaining a
> postgresql-centric web application since postgresql 7.0 and now I am
> learning that by writing my sql in this fashion I am constricting the
> planner. After reading this:
>
> http://marc.theaimsgroup.com/?l=postgresql-general&m=105551123915183&w=2
>
> I am wondering if things are going to change in 7.4?  Or should I switch
> to placing joins in the where clause when I can?  I don't want to have
> to worry about my join order-- I would prefer to let the planner do its
> thing 95% of the time.

Currently using the explicit join syntax forces join order. In 7.4 it
won't (unless you change a setting). So for you, 7.4 should be an improvement.

culley harrelson <culley@fastmail.fm> writes:
> http://marc.theaimsgroup.com/?l=postgresql-general&m=105551123915183&w=2
> I am wondering if things are going to change in 7.4?

Did you actually read the cited links?

            regards, tom lane

> Did you actually read the cited links?
>

I read the 7.3 docs then fired off an email and forgot about 7.4 docs.
duh!  sorry.