尝试使用||更新表中的JSONB列运算符，然后使用now或current_timestamp插入当前时间，但不能。

我的jsonb_column结构是

{
  "status": "oldStatus","statusUpdatedTimestamp": null //this field might be present or not,if it's present it has to be overwritten. if not,it has to be added
}

create or replace function update_jsonb() 
returns trigger language plpgsql 
as $function$ 
begin 
    if (TG_OP = 'UPDATE' and old.jsonb_column ->> 'status' <> new.jsonb_column ->> 'status') then 
        --need statusUpdatedTimestamp to have the current time
        new.jsonb_column = new.jsonb_column || '{"statusUpdatedTimestamp": ' now ' }';
    end if;

    return new;
end;
$function$ ;

我对jsonb_column的预期输出是

{
  "status": "newStatus","statusUpdatedTimestamp": '2019-12-11 10:10:35'
}