Обсуждение: Re: 'a' == 'a ' (Was: RE: [pgsql-advocacy] Oracle buys

Tino Wildenhain wrote:

>>>>
>>>> Then we are broken too :)
>>>>
>>>> # select 'a ' = 'a  ';
>>>>   ?column?
>>>> ----------
>>>>   f
>>>> (1 row)
>
>
> experiment=# SELECT 'a '::char = 'a  '::char;
>  ?column?
> ----------
>  t
>

This does't show anything useful, because the ::char casting simply
takes the first char of any string:

select 'abc'::char = 'axy'::char

Also results in 'true'.  Hopefully no one in this discussion would want
those two strings to be equal.

--
Guy Rouillier

"Guy Rouillier" <guyr@masergy.com> writes:

> Tino Wildenhain wrote:
> >
> > experiment=# SELECT 'a '::char = 'a  '::char;
> >  ?column?
> > ----------
> >  t
> >
>
> This does't show anything useful, because the ::char casting simply
> takes the first char of any string:
>
> select 'abc'::char = 'axy'::char
>
> Also results in 'true'.  Hopefully no one in this discussion would want
> those two strings to be equal.

A better experiment:

db=> select 'a '::char(3) = 'a  '::char(3);
 ?column?
----------
 t
(1 row)

--
greg