RE: next baby step in SQL: start using join

["Goodbar, Loyd (ETS - Water Valley)" <LGoodbar@xxxxxxxxxxxxxx>]

I think it is cleaner to use both the JOIN clause. Before the JOIN clause
was added to SQL, you had to use the "theta" method, which placed everything
in the WHERE clause. After the JOIN clause was added, it separates your SQL
statement into logical parts.

JOIN shows HOW the files work together.
WHERE shows WHICH selection criteria to use.

I look at the older theta-style statements and see a lot of "noise" areas
(such as where a.column=b.column) that have nothing to do with running the
selection criteria. I much prefer the JOIN syntax.

Loyd

--
Loyd Goodbar
Programmer/analyst
BorgWarner Incorporated
ETS/Water Valley
662-473-5713


-----Original Message-----
From: Dan [mailto:dbcemid@xxxxxxxxx] 
Sent: Friday, March 28, 2003 9:21 AM
To: Midrange Systems Technical Discussion
Subject: Re: next baby step in SQL: start using join


Ok, guys, I'm seeing two schools of thought here.  Dave & Gord say to let
the WHERE do the "joining", whereas Rick suggests using JOIN and taking care
of file placement in the join.

Gord also mentions that using WHERE will cause the query optimizer to
determine the best path.

I suppose it gets into personal opinion, but, in this example anyway, I find
using the JOIN makes it more apparent that you are joining files and how you
are joining them.  (vs. using WHERE to do the join.)

Comments and advice are welcome & appreciated.

- Dan