Обсуждение: create operator problem

Hello!

I use an external function in postgres and here i try create operator for
like with regional character support ::

-----< Cut begin
create function mylike(text,text) returns bool
as '/home/vip/neko/tudakozo/comp.so' language 'c';
CREATE
select mylike('Jeno','Jen�'),mylike('aJenO','Jen�'),mylike('fJeNof','Jen�'),
       mylike('JEn�ke','Jen�');
mylike|mylike|mylike|mylike
------+------+------+------
t     |t     |t     |t
(1 row)

select 'f:', mylike('asd','fds');
?column?|mylike
--------+------
f:      |f
(1 row)

-- It works

drop operator ~~ (text,text);
DROP
create operator ~~ (leftarg=text,rightarg=text,procedure=mylike);
CREATE
select 'this will be true'::text ~~ 'true';
?column?
--------
f
(1 row)
-- it seems not ;(
-----< Cut end

I'm not a realy postgres guru, but whith postgres 6.2 can i use this
function as operator too. If that was a bug, this letter is a bug report,
but if it isn't please help me!  The used postgres's vn: 6.3-2, it runs on a
linux (RH4.2;i386 + updates)

sprintf         ("`-''-/").___..--''"`-._            Error In
("%|s",          `6_ 6  )   `-.  (     ).`-.__.`)    Loading Object
"Petike"         (_Y_.)'  ._   )  `._ `. ``-..-'     line:3
/* Neko */     _..`--'_..-_/  /--'_.' ,'             Before /*Neko*/
 );           (il),-''  (li),'  ((!.-'     see: http://lsc.kva.hu

"Vazsonyi Peter[ke]" <neko@kornel.szif.hu> writes:

> drop operator ~~ (text,text);
> DROP
> create operator ~~ (leftarg=text,rightarg=text,procedure=mylike);
> CREATE
> select 'this will be true'::text ~~ 'true';
> ?column?
> --------
> f
> (1 row)
> -- it seems not ;(

I got bitten by this, too.  There's special handling of ~~ hardcoded
into the parser, which expects that it implements the vanilla flavor
of likeness testing.  It has to do with enabling the use of indices to
speed up the matching.  Bottom line: you can't redefine it.

-tih
--
Popularity is the hallmark of mediocrity.  --Niles Crane, "Frasier"

>
> Hello!
>
> I use an external function in postgres and here i try create operator for
> like with regional character support ::
>
> -----< Cut begin
> create function mylike(text,text) returns bool
> as '/home/vip/neko/tudakozo/comp.so' language 'c';
> CREATE
> select mylike('Jeno','Jen�'),mylike('aJenO','Jen�'),mylike('fJeNof','Jen�'),
>        mylike('JEn�ke','Jen�');
> mylike|mylike|mylike|mylike
> ------+------+------+------
> t     |t     |t     |t
> (1 row)
>
> select 'f:', mylike('asd','fds');
> ?column?|mylike
> --------+------
> f:      |f
> (1 row)
>
> -- It works
>
> drop operator ~~ (text,text);
> DROP
> create operator ~~ (leftarg=text,rightarg=text,procedure=mylike);
> CREATE
> select 'this will be true'::text ~~ 'true';
> ?column?
> --------
> f
> (1 row)
> -- it seems not ;(
> -----< Cut end
>
> I'm not a realy postgres guru, but whith postgres 6.2 can i use this
> function as operator too. If that was a bug, this letter is a bug report,
> but if it isn't please help me!  The used postgres's vn: 6.3-2, it runs on a
> linux (RH4.2;i386 + updates)

We overload ~~ to allow indexing of LIKE operations.  Sorry.  I will add
something to error on redefine of ~~.

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