2015-08-29 19:11 GMT+02:00 Andrew Dunstan <and...@dunslane.net>: > > > On 08/29/2015 12:02 PM, Pavel Stehule wrote: > >> >> >> 2015-08-29 15:43 GMT+02:00 Shulgin, Oleksandr < >> oleksandr.shul...@zalando.de <mailto:oleksandr.shul...@zalando.de>>: >> >> On Sat, Aug 29, 2015 at 3:39 PM, Tom Lane <t...@sss.pgh.pa.us >> <mailto:t...@sss.pgh.pa.us>> wrote: >> >> Andrew Dunstan <and...@dunslane.net >> <mailto:and...@dunslane.net>> writes: >> > On 08/29/2015 08:47 AM, Shulgin, Oleksandr wrote: >> >> Given there were no loud complaints about this, the current >> behavior >> >> is appropriate for most users, the rest can still work >> around using >> >> coalesce(to_json(...), json 'null'). >> >> > I don't think it's necessarily more correct. But I do agree >> that it's >> > not a good idea to change the behaviour unless there is major >> > unhappiness with it. >> >> I'm not entirely convinced that JSON NULL and SQL NULL should >> be treated >> as the same concept, so I would say that the current behavior >> is fine --- >> at least when you think about it in isolation. However, >> haven't we >> already bought into that equivalence in these examples? >> >> regression=# select row_to_json(row(1,null,2)); >> row_to_json >> --------------------------- >> {"f1":1,"f2":null,"f3":2} >> (1 row) >> >> regression=# select array_to_json(array[1,null,2]); >> array_to_json >> --------------- >> [1,null,2] >> (1 row) >> >> or even in to_json itself: >> >> regression=# select to_json(array[1,null,2]); >> to_json >> ------------ >> [1,null,2] >> (1 row) >> >> The scalar case is definitely failing to be consistent with these. >> >> >> Yes, that's my argument for correctness also: to_json() on a >> composite object should behave like distribution of to_json() >> calls over object/array elements. >> >> Is consistency a sufficient reason to change it? >> >> >> Not for me. >> >> >> It is bug - and it should be fixed. I agree, so this change is too strong >> for fixing in minor version - but we can change it in unreleased major >> versions - 9.5 and master. >> > > > > > No, frankly that's being far too free with the word bug. It's not even > unambiguously incorrect. > > Note that all the to_json functions are strict. In this sense it's quite > consistent. If we change it to being called on null input, what should we > return if a null non-scalar is passed in? >
what is correct from JSON perspective? All fields with NULL Pavel > > cheers > > andrew > >
