Re: [HACKERS] SELECT BUG

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От Bruce Momjian
Тема Re: [HACKERS] SELECT BUG
Дата
Msg-id 199909071539.LAA03078@candle.pha.pa.us
обсуждение исходный текст
Ответ на Re: [HACKERS] SELECT BUG  (José Soares <jose@sferacarta.com>)
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[Charset iso-8859-1 unsupported, filtering to ASCII...]
> 
> 
> Tom Lane ha scritto:
> 
> > José Soares <jose@sferacarta.com> writes:
> > > And now the other SELECT bug in the same data:
> > > select master1.*, detail1.*
> > > from master1 m, detail1 d
> > > where trim(m.code)=trim(d.code);
> >
> > This one is definitely pilot error.  Since you've renamed master1 and
> > detail1 in the FROM clause, your use of the original names in the SELECT
> > list is treated as adding more FROM items.  Effectively your query is
> >
> > select m2.*, d2.*
> > from master1 m, detail1 d, master1 m2, detail1 d2
> > where trim(m.code)=trim(d.code);
> >
> > You're getting a four-way join with only one restriction clause...
> >
> > There was a thread just the other day about whether we ought to allow
> > queries like this, because of someone else making exactly the same
> > error.  I believe allowing tables to be referenced without FROM entries
> > is a holdover from the old Postquel language that's not found in SQL92.
> > Maybe we should get rid of it on the grounds that it creates confusion.
> >
> >                         regards, tom lane
> >
> >
> 
> PostgreSQL should raise a syntax error like Informix and Oracle do.


We sould at least give them an elog(NOTICE) to say we are doing
something special, no?


> 
> > ************
> > INFORMIX:
> >
> > select master1.*, detail1.* from master1 m, detail1 d where mcode=dcode;
> > #              ^
> > #  522: Table (master1) not selected in query.
> > #
> > ------------------------------------------------------------------------
> > ORACLE:
> >
> > select master1.*, detail1.* from master1 m, detail1 d where mcode=dcode
> >  *
> > ERROR at line1:
> > ORA-00942: table or view does not exist
> >
> >
> 
> Jos_
> 
> 
> ************
> 
> 


--  Bruce Momjian                        |  http://www.op.net/~candle maillist@candle.pha.pa.us            |  (610)
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