Path: utzoo!utgpu!water!watmath!clyde!rutgers!im4u!ut-sally!ut-emx!lad-shrike!chris
From: chris@AUSTIN.LOCKHEED.COM (Chris Wood)
Newsgroups: comp.databases
Subject: Re: Informix query
Summary: SQL limitations
Message-ID: <71@coot.AUSTIN.LOCKHEED.COM>
Date: 12 Jan 88 14:03:49 GMT
References: <3072@ihlpf.ATT.COM> <3890001@hpcmmb.HP.COM> <3216@ihlpf.ATT.COM> <29265UH2@PSUVM>
Organization: Lockheed Austin Div.
Lines: 36
Posted: Tue Jan 12 08:03:49 1988

In article <29265UH2@PSUVM>, UH2@PSUVM.BITNET (Lee Sailer) writes:
> I've never used any SQL product, but supposedly know some of the underlying
> ideas.  How about something like
>      
> good customers = Select count(id#)
>                  FROM customers
>                  WHERE area = NORTHEAST and qty.ordered > 1000
> >
>      
> For the total orders problem, try something like
>      
> SELECT number, sum(amount)
> FROM customers, orders
> WHERE custno = number
> GROUP BY number
>      
> and define customers.totalamt = SELECT tamt FROM t
>                                 WHERE customers.number=t.number
>      

All of this is fairly close, but the point is that I could do it in
1 query with M204, but a single query in SQL can only do a single thing.
This means that if I want to do several things to the same set of
records, I must re-retrieve those records for each function.  I guess this
kind of grates against the "traditional" programmer in me that still
yearns for a modicum of efficiency.  It is obviously simpler to do one
thing at a time, but it bothers me to repeat work.  Once I have located
and retrieved a set of data, I really don't want to have to do it all over
again just because the query language forces me into it!  I am now convinced
that this is not a problem with "relational", it is a problem with SQL.

Question: I am (embarassingly) unfamiliar with CURSORS.  Will they 
solve some of this problem?


Chris Wood