On 2022-07-08 Fr 07:57, Dagfinn Ilmari Mannsåker wrote:
> Erik Rijkers <er@xs4all.nl> writes:
>
>> Hi,
>>
>> Comparison of 2 values of type jsonb is allowed.
>>
>> Comparison of 2 values of type json gives an error.
>>
>> That seems like an oversight -- or is it deliberate?
> This is because json is just a textual representation, and different
> JSON strings can be semantically equal because e.g. whitespace and
> object key order is not significant.
>
>> Example:
>>
>> select '42'::json = '{}'::json;
>> --> ERROR: operator does not exist: json = json
>>
>> (of course, easily 'solved' by casting but that's not really the
>> point)
> To do a proper comparison you have to parse it into a semantic form,
> which is what casting to jsonb does.
Alternatively, if you really need something like this, try
<https://bitbucket.org/adunstan/jsoncmp/src/master/>
(I should probably update it to mark the functions as parallel safe)
cheers
andrew
--
Andrew Dunstan
EDB: https://www.enterprisedb.com