SQL SELECT MAX（COUNT）

Question

我想選擇誰擁有用戶的最大數微觀柱：

SELECT "name", count(*) FROM "users" 
    INNER JOIN "microposts" ON "microposts"."user_id" = "users"."id" 
    GROUP BY users.id 

，這將返回

"Delphia Gleichner";15 
"Louvenia Bednar IV";10 
"Example User";53 
"Guadalupe Volkman";20 
"Isabella Harvey";30 
"Madeline Franecki II";40 

但我只想選擇"Example User";53，（用戶誰有MAX微博計數）

我試圖添加HAVING MAX(count*)，但這沒有奏效。

Answer 1

我想嘗試用ORDER BY最大DESC LIMIT 1，其中最大的是COUNT（*）領域。喜歡的東西：

SELECT "name", count(*) maximum FROM "users" 
    INNER JOIN "microposts" ON "microposts"."user_id" = "users"."id" 
GROUP BY users.id 
ORDER BY maximum DESC 
LIMIT 1 

我不」具有的MySQL現在，所以我在紙上做這（和它可能無法正常工作），但它只是一個方向。

Answer 2

也許是這樣的：

SELECT "name", count(*) 
FROM "users" 
INNER JOIN "microposts" ON "microposts"."user_id" = "users"."id" 
GROUP BY users.id 
HAVING COUNT(microposts) = (SELECT COUNT(microposts) 
         FROM users 
         GROUP BY microposts 
         ORDER BY COUNT(microposts) DESC 
         LIMIT 1) 

沒有測試它，但它可能工作

Answer 3

SELECT TOP 1 "name", count(*) AS ItemCount FROM "users" 
INNER JOIN "microposts" ON "microposts"."user_id" = "users"."id" 
GROUP BY users.id 
ORDER BY ItemCount DESC 

Answer 4

SELECT x.name, MAX(x.count) 
FROM (
SELECT "name", count(*) 
    FROM "users" INNER JOIN "microposts" ON "microposts"."user_id" = "users"."id" 
    GROUP BY users.id 
) x 

Answer 5

這很簡單，你可以嘗試：

SELECT "name", MAX(count_num) FROM 
(SELECT "name", count(*) as count_num 
FROM "users" INNER JOIN "microposts" ON "microposts"."user_id" = "users"."id" 
GROUP BY users.id) x