Re: more on delete from join
From: paul c <toledobythesea_at_oohay.ac>
Date: Wed, 26 Aug 2009 23:03:06 GMT
Message-ID: <Kajlm.40829$Db2.37871_at_edtnps83>
>
> Can you express the difference formally? I would insist relations and
> predicates being the same thing. ...
Date: Wed, 26 Aug 2009 23:03:06 GMT
Message-ID: <Kajlm.40829$Db2.37871_at_edtnps83>
Tegiri Nenashi wrote:
> On Aug 26, 2:14 pm, paul c <toledobythe..._at_oohay.ac> wrote:
>> Tegiri Nenashi wrote: >>> On Aug 26, 1:03 pm, paul c <toledobythe..._at_oohay.ac> wrote: >>>> I meant "AND" as the logical connective, not shorthand for relational >>>> "<AND>". "R AND A" stands for a logical conjunction of propositions, >>>> each proposition having been concluded to be true. >>> Stop right there. You were writing R UNION A, so R and A are relations >>> (or predicates) and not propositions. ... >> Okay, I'll stop right there and be even more precise, relations are not >> predicates, they are representations of predicates.
>
> Can you express the difference formally? I would insist relations and
> predicates being the same thing. ...