"Nikolay Samokhvalov" <[EMAIL PROTECTED]> writes:
> CREATE CAST (aaa AS text) WITHOUT FUNCTION
>       AS IMPLICIT;
> CREATE CAST (text AS aaa) WITHOUT FUNCTION
>       AS IMPLICIT;

> trash=# select ('as' || 'df')::aaa;
>  aaa  
> ------
>  asdf
> (1 row)

> In the last case, function aaa_in() wasn't invoked at all and we obtained 
> the sting of type aaa with length > 3...

Well, sure.  You declared the text to aaa cast as WITHOUT FUNCTION; that
says the system can relabel any legal text value as an aaa.  If you want
to enforce a length limit on the cast result, you need to write a cast
function that does it.

                        regards, tom lane

---------------------------(end of broadcast)---------------------------
TIP 1: if posting/reading through Usenet, please send an appropriate
       subscribe-nomail command to [EMAIL PROTECTED] so that your
       message can get through to the mailing list cleanly

Reply via email to