json - Test datatype on postgresql update trigger -

i use trigger detect if @ least 1 value has changed when update performed on table.

the function :

create or replace function update_version_column()   returns trigger $body$ begin     if row(new.*) distinct row(old.*)         new.version = now();          return new;     else         return old;     end if; end; $body$   language plpgsql volatile   cost 100; alter function update_version_column()   owner gamesplateform; 

the problem is, when column type "json", "is distinct" failed (standard comportement, explained in documentation).

i search way perform same thing, if column in "json" type, want force "jsonb" cast accept comparison operator.

is there way ?

thanks !

found way :

create or replace function update_version_column()   returns trigger $body$  declare     updated boolean := false;     column_data record;  begin      column_data in          select         column_name::varchar,         data_type::varchar         information_schema.columns c         table_name = tg_table_name     loop         if column_data.data_type = 'json'             execute format('select case when ($1).' || column_data.column_name || '::text <> ($2).' || column_data.column_name || '::text true else false end')              using new, old             updated;         else             execute format('select case when ($1).' || column_data.column_name || ' <> ($2).' || column_data.column_name || ' true else false end')             using new, old             updated;         end if;         if updated = true             new.version := now();             return new;         end if;     end loop;      return old; end; $body$   language plpgsql volatile   cost 100; alter function update_version_column()   owner gamesplateform; 

i cast "json" in "text" because have fail "jsonb" (type not exist). seems specific configuration, trigger answers great :)

thanks @julien bossart !