如何在单个查询中选择两个计数？

Question

我在使用php工作的这一件事上遇到了一些麻烦（尽管我认为这并不重要）。

我有一张名为apples的表格。它有一个名为good apples的列，其值为0 or 1。我想做一个sql查询，我想用它来显示该表中的总苹果中的good apples=1。我如何计算单个查询中的ALL和good apples=1，如果这样做的话？

Answer 1

您始终可以使用MySQL条件计数。

SELECT 
    COUNT(goodapples) as totalCount, 
    COUNT(CASE WHEN apples.goodapples = 1 THEN 1 END) 
AS 
    goodapplecount 
FROM 
    apple;

Answer 2

试试这个：

select sum(good_apples) as good_count, count(*) as all_count from apples

Answer 3

我想这样做：

 SELECT SUM(good_apples), count(good_apples) FROM apple_table

Answer 4

您可以执行以下操作：

SELECT b_good_apple, COUNT(b_good_apple) AS apple_count FROM apples
GROUP BY b_good_apple;

这样你才能获得“好苹果”和“坏苹果”的重要性。显然，两者的总和就是你的总和。

Answer 5

 SELECT count(*) as count,sum(good_apple) FROM `Apple` 

Answer 6

试试这个......

SELECT COUNT(good_apples) AS goodApples 
    FROM apples WHERE good_apples = 1 
    UNION SELECT COUNT(*) AS totalApples FROM apples