綁定多個查詢到一個結果

Question

任何人可以幫助我得到的結果形式多個SQL請求：

SELECT * 
(COUNT(*) AS Records FROM wp_posts WHERE post_type='news' AND post_status='publish') as News, 
(COUNT(*) AS Records FROM wp_posts WHERE post_type='promotion' AND post_status='publish') as Promos, 
(COUNT(*) AS Records FROM wp_posts WHERE post_type='contact' AND post_status='publish') as Contacts 
FROM wp_posts 

我只是想通過發送一個SQL請求，找出定製我的WP MySQL的多少職位。

Answer 1

沒有必要在子查詢所有：

SELECT 
    SUM(CASE WHEN post_type='news' THEN 1 ELSE 0 END) AS News, 
    SUM(CASE WHEN post_type='promotion' THEN 1 ELSE 0 END) AS Promos, 
    SUM(CASE WHEN post_type='contact' THEN 1 ELSE 0 END) AS Contacts 
FROM wp_posts 
WHERE post_status='publish'; 

甚至更​​短：

SELECT 
    SUM(IF(post_type='news', 1, 0)) AS News, 
    SUM(IF(post_type='promotion', 1, 0)) AS Promos, 
    SUM(IF(post_type='contact', 1, 0)) AS Contacts 
FROM wp_posts 
WHERE post_status='publish'; 

Answer 2

使用UNION ALL到查詢組合（他們需要有相同的列數）

SELECT * FROM (
SELECT 1 
UNION ALL 
SELECT 2 
) 

Answer 3

可以發出一個與三個嵌套SELECT查詢選擇和得到的結果爲列：

SELECT 
(SELECT COUNT(*) FROM wp_posts WHERE post_type='news' AND post_status='publish') as News, 
(SELECT COUNT(*) FROM wp_posts WHERE post_type='promotion' AND post_status='publish') as Promos, 
(SELECT COUNT(*) FROM wp_posts WHERE post_type='contact' AND post_status='publish') as Contacts