找到兩個不同的查詢總數之間的差額SQL

Question

我有一個表Vocab，我想找到總行和重複數的數量，這是我想

(SELECT COUNT(*) FROM Vocab) - (SELECT COUNT(*) FROM Vocab GROUP BY Word) 的代碼，但它返回我錯誤Unexpected token. (near "-" at position 29)，我怎樣才能實現我的目標？

Answer 1

我想你想count(distinct)和一些算術：

select count(*) as total_words, 
     count(distinct word) as total_distinct_words, 
     (count(*) - count(distinct word)) as must_be_duplicated 
from Vocab;