Обсуждение: How to create a type ?

Hello,

I am trying to understand how works CREATE TYPE, but it seems to
be too difficult for me...

Can someone help me ?

I have tried this :
----------------------------------
create function personne_in(text)
returns personne
as 'select $1;'
language 'sql';

create function personne_out(text)
returns text
as 'select $1;'
language 'sql';

create type personne (
internallength = variable,
input = personne_in,
output = personne_out
);
---------------------------------
but it is full of mistakes.

Even a simple example in language 'sql' will help me.

Thanks,
Ines.

Ines Klimann <Ines.Klimann@liafa.jussieu.fr> writes:
> I have tried this :
> ----------------------------------
> create function personne_in(text)
> returns personne
> as 'select $1;'
> language 'sql';

> create function personne_out(text)
> returns text
> as 'select $1;'
> language 'sql';

> create type personne (
> internallength = variable,
> input = personne_in,
> output = personne_out
> );
> ---------------------------------
> but it is full of mistakes.

Can't do it that way, because SQL functions can't produce or consume
the plain C strings that input/output conversion functions have to
deal with.  There's really no way to write an input or output function
except in C.
        regards, tom lane

hope it helps.
e.g.
create function foo() returns setof varchar as '
select name from categories '
language 'sql';
db=# select foo() as name;             name               
---------------------------------recreationbusinesswebeducationquestionablesexsocialsocietyweapons/bombsmature
humorpornographytastelesscomputerhackingnuditydrugslingerie/bikiniprofanity
 
.......


Jie LIANG

St. Bernard Software
Internet Products Inc.

10350 Science Center Drive
Suite 100, San Diego, CA 92121
Office:(858)320-4873

jliang@ipinc.com
www.stbernard.com
www.ipinc.com

On Tue, 13 Feb 2001, Ines Klimann wrote:

> Hello,
> 
> I am trying to understand how works CREATE TYPE, but it seems to
> be too difficult for me...
> 
> Can someone help me ?
> 
> I have tried this :
> ----------------------------------
> create function personne_in(text)
> returns personne
> as 'select $1;'
> language 'sql';
> 
> create function personne_out(text)
> returns text
> as 'select $1;'
> language 'sql';
> 
> create type personne (
> internallength = variable,
> input = personne_in,
> output = personne_out
> );
> ---------------------------------
> but it is full of mistakes.
> 
> Even a simple example in language 'sql' will help me.
> 
> Thanks,
> Ines.
>