Subject: | Re: date grief
| Date: | Tue, 5 Dec 2017 20:44:56 +1000
| From: | Bernie van't Hof <berniev@bje.com.au>
| Newsgroups: | pnews.paradox-dos
|
Cool.
I have papers describing the original '70's IBM methodology of QBE and
the later M$ Access subset but didn't know there was such a thing as a
"standard".
Clearly ANSA/Borland famously took qbe to a new practical level. Clever
buggers those ANSA/Borland people. But after that it just sort of died.
I find it particularly fascinating that SET operations are not supported
by Access or pdoxwin sql converter. I do have a 2011 paper describing
just how difficult it is to translate SET queries to SQL. Something to
do with the inherent design of SQL.
But the world has long since moved to SQL type databases ..
Who was it said nothing worthwhile is ever simple?
I have not found a qbe parser, open source or otherwise. Probably
because QBE has lost favour. As I try to understand the operation of
QBE I can kind of understand why: The abstractions introduced are quite
difficult to document and very implementation dependent. I recall over
many years that one would try different things to find something that
"worked", perhaps without ever fully understanding why. A more literal
approach like sql is easier to understand and even that has some obscure
outcomes. Just my 2c.
- Bernie
On 5/12/17 5:56 pm, Leslie wrote:
> Not on hand, I would have to go back to my Borland white papers from the
> 80's. I did scan a whole heap of stuff and archive it so I may have an
> old copy from about 1991-ish.
>
> But are you saying that the QBE definition is not online somewhere?
>
> Come to think of it has anyone done any searches for an existing qbe
> parser. I haven't but perhaps someone has written one already.
>
> When I get some time I will see what I can find out.
> Leslie.
>
> On 5/12/2017 5:43 PM, Bernie van't Hof wrote:
>> If you have a copy I'd be more than happy to have a look..
>>
>> On 5/12/17 4:53 pm, Leslie wrote:
>>> QBE parser as per the standard
>
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