Re: Bug in create operator and/or initdb

The following seems to me a bug in either initdb or create operator:

CREATE FUNCTION my_func (inet, inet) as '$libdir/my_func.so' LANGUAGE 'C' IMMUTABLE STRICT;
CREATE OPERATOR <<< (
PROCEDURE = my_func,
LEFTARG = cidr,
RIGHTARG = cidr,
RESTRICT = contsel,
JOIN = contjoinsel
);

ERROR: function my_func(cidr, cidr) does not exist

Now, if you look at the catalog, and the < (less than operator) as an example you will see that:

Two operators are defined for < - one for inet,inet and another for cidr,cidr.
Only one function exists named network_lt, and is declared as taking (inet,inet) as arguments.

Obviously, it should either have a corresponding function declaration, or it should be possible to create the operators using a binary compatible function (eg: where a binary compatible cast exists).

I propose, that the create operator syntax be modified to accept:

PROCEDURE = function_name (type{,type})

and that checks be made for the existence of binary compatible casts between the two (four) types.

Kind Regards,

John

"John Hansen" <john(at)geeknet(dot)com(dot)au> writes:
> CREATE FUNCTION my_func (inet, inet) as '$libdir/my_func.so' LANGUAGE 'C' IMMUTABLE STRICT;
> CREATE OPERATOR <<< (
> PROCEDURE = my_func,
> LEFTARG = cidr,
> RIGHTARG = cidr,
> RESTRICT = contsel,
> JOIN = contjoinsel
> );

> ERROR: function my_func(cidr, cidr) does not exist

Right ...

> Now, if you look at the catalog, and the < (less than operator) as an example you will see that:

> Two operators are defined for < - one for inet,inet and another for cidr,cidr.
> Only one function exists named network_lt, and is declared as taking (inet,inet) as arguments.

My opinion is that this is a very bogus shortcut in the network datatype
code. There are no cases outside the inet/cidr group where an operator
doesn't exactly match its underlying function. (The whole business of
inet and cidr being almost but not quite the same type is maldesigned
anyway...)

The right solution for you is to declare two SQL functions. Whether you
make them point at the same underlying C code is up to you.

regards, tom lane