LightDB-A 兼容oracle支持mod操作符

LightDB-A 为了兼容oracle，从23.3版本开始支持mod操作符，其语义同 ‘%’ 操作符，使用案例如下：

select 5 mod 2;
 ?column? 
----------
        1
(1 row)


select 0 % 0;
ERROR:  division by zero

select 5 % 0;
ERROR:  division by zero

select -1 % 0;
ERROR:  division by zero

select -1 % 2;
 ?column? 
----------
       -1
(1 row)

select -1 % 3;
 ?column? 
----------
       -1
(1 row)

select -2 % 3;
 ?column? 
----------
       -2
(1 row)


do $$
DECLARE
id int;
begin
    id := 7 mod 4;
    RAISE NOTICE 'id = %', id;
end;
$$;

NOTICE:  id = 3
DO