Re: GSoC 2017: Foreign Key Arrays

On Wed, Jul 12, 2017 at 12:53 AM, Alvaro Herrera <alvherre(at)2ndquadrant(dot)com>
wrote:
>
> We have one opclass for each type combination -- int4 to int2, int4 to
> int4, int4 to int8, etc. You just need to add the new strategy to all
> the opclasses.

I tried this approach by manually declaring the operator multiple of times
in pg_amop.h (src/include/catalog/pg_amop.h)

so instead of the polymorphic declaration
DATA(insert ( 2745 2277 2283 5 s 6108 2742 0 )); /* anyarray @>> anyelem
*/

multiple declarations were used, for example for int4[] :
DATA(insert ( 2745 1007 20 5 s 6108 2742 0 )); /* int4[] @>> int8 */
DATA(insert ( 2745 1007 23 5 s 6108 2742 0 )); /* int4[] @>> int4 */
DATA(insert ( 2745 1007 21 5 s 6108 2742 0 )); /* int4[] @>> int2 */
DATA(insert ( 2745 1007 1700 5 s 6108 2742 0 ));/* int4[] @>> numeric */

However, make check produced:
could not create unique index "pg_amop_opr_fam_index"
Key (amopopr, amoppurpose, amopfamily)=(6108, s, 2745) is duplicated.

Am I implementing this the wrong way or do we need to look for another
approach?