select
	imm.PORT_CODE as '港コード',
	po.PORT_NAME as '港名',
	sum(
	case
	when imm.KIND_CODE = '110' then AMT else 0 end	
	) as '入国者数',

	sum(
	case
	when imm.KIND_CODE = '120' then AMT else 0 end	
	) as '出国者数',
	
	sum(
	case
	when imm.KIND_CODE = '110' then AMT else 0 end	
	) 
	- sum(
	case
	when imm.KIND_CODE = '120' then AMT else 0 end	
	) as '差分'
from
	IMMIGRATION as imm
	left join PORT as po
	using(PORT_CODE)
where imm.group_code = 120
group by imm.PORT_CODE
having 0 < 差分
order by 5 desc,1
;