我现在的问题是取不出没有县级城市的市

(
select 

c.dc_province_city_d_id p1,

c.pc_name n1,
b.dc_province_city_d_id p2,

b.pc_name n2
from dc_province_city_d a 
left join dc_province_city_d b on a.parent_id=b.dc_province_city_d_id
left join dc_province_city_d c on b.parent_id=c.dc_province_city_d_id
where c.parent_id=0 and b.dc_province_city_d_id='${D5}'
)
union all
(select 

c.dc_province_city_d_id p1,

c.pc_name n1,
a.dc_province_city_d_id p2,

a.pc_name n2
from dc_province_city_d a 
left join dc_province_city_d b on a.parent_id=b.dc_province_city_d_id
left join dc_province_city_d c on b.parent_id=c.dc_province_city_d_id
where c.parent_id=0 and c.dc_province_city_d_id='${D5}'
)

最终p1为省id,n1为省名称

p2为市和县id,n2为市和县名称