[ Moved to pgsql-general. pgsql-hackers is for development of PostgreSQL itself. ] On Mon, 2011-07-25 at 20:06 -0300, Alexandre Savaris wrote: > ********** Error ********** > > ERRO: input function 49344 returned NULL > SQL state: XX000 > Character: 45 > > It seems like the call to PG_RETURN_NULL() on the input function is > causing the error. Is this the correct behaviour? There's another way to > return a NULL value as the result of a data type's input function? The docs say: "The input function must return a value of the data type itself." http://www.postgresql.org/docs/9.0/static/sql-createtype.html Which means you can't return a NULL from the input function when there is non-NULL input. The context around that statement is a little more informative, but perhaps it could be more clear. I assume that postgresql has that requirement because it needs to know whether something is NULL without necessarily knowing what type it is. For instance: ' ' IS NULL Should that be true or false? If it depends on the type of the left-hand-side, how do you figure out what type it is? I'm not sure if this is the exact reason it's prohibited, but it seems like there would be a problem somewhere along these lines. Interesting idea though. Regards, Jeff Davis -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
