如何計算MySQL中非唯一的值組合？

Question

我有一張表格，裏面有一些遺留數據，我懷疑可能會有些混亂。這是一個多對多的連接表。

LIST_MEMBERSHIPS 
---------------- 
list_id 
address_id 

我想運行一個查詢，將統計每個list_id的出現 - address_id對，並顯示出發生從最高計數每到最低出現的次數。

我知道它需要涉及COUNT()和GROUP BY，對吧？

Answer 1

select list_id, address_id, count(*) as count 
from LIST_MEMBERSHIPS 
group by 1, 2 
order by 3 desc 

您可能會發現它有用添加

having count > 1 

Answer 2

select count(*), list_id, address_id 
from list_membership 
group by list_id, address_id 
order by count(*) desc