Json operators treat pguint as strings...

[NoMoreNicksLeft]

create table crap (test integer);
CREATE TABLE
insert into crap values (456);
INSERT 0 1
select row_to_json(crap) as j from crap;
      j
--------------
 {"test":456}

But if instead I use...

create table crap2 (test uint4);
CREATE TABLE
insert into crap2 values (456);
INSERT 0 1
select row_to_json(crap2) as j from crap2;
       j
----------------
 {"test":"456"}

This is a minor nitpick of course. I was hoping that there's some clever create cast statement that will resolve the issue. Or would a solution need to be more involved than this?

[ranvis]

Source code says cast to json is looked up:
https://github.com/postgres/postgres/blob/24e2885ee304cb6a94fdfc25a1a108344ed9f4f7/src/backend/utils/adt/json.c#L206

create function json(uint4) returns json as 'select $1::text::json;' language sql immutable returns null on null input;
create cast (uint4 as json) with function json(uint4);
select row_to_json(crap2) as j from crap2;
      j
--------------
 {"test":456}

Though I don't know if it is optimal, this seems to work.

[NoMoreNicksLeft]

Thanks @ranvis . This is awesome. This will be a big help for me actually.