從同一個表

Question

選擇不同的結果，我在後表結構如下（舉例）：

id | id_author | content | date | ft 
1 | 1   | hi!  | 2016 | 2 
2 | 1   | hello! | 2016 | 3 
3 | 1   | welcome | 2016 | 1 
4 | 1   | test! | 2016 | 2 

，我已經在query：

SELECT id, id_author, content, date, ft FROM post where id_author = '$author' ORDER BY id DESC LIMIT 7 

但是，我也需要select與各自ft與LIMIT 4的帖子。就像這樣：

SELECT id, id_author, content, date, ft FROM post where id_author = '$author' and ft = 1 ORDER BY id DESC LIMIT 4 

SELECT id, id_author, content, date, ft FROM post where id_author = '$author' and ft = 2 ORDER BY id DESC LIMIT 4 

SELECT id, id_author, content, date, ft FROM post where id_author = '$author' and ft = 3 ORDER BY id DESC LIMIT 4 

我可以做的ft 「過濾器」 與foreach，例如：

foreach($query as $ex) { 
    switch($ex["ft"]) { 
     ... 
    } 
} 

但是，我的第一個query需要有LIMIT 7和querys realtives到ft需要從中選擇最後4個結果全部的帖子。

如何做到這一點，而不必做多倍querys？

編輯：

我需要顯示在過去的7個（一般）在一個div，最後4個帶有圖片的帖子（ft = 1）在另一個div，最後4個員額，在提到（ft = 2）另一個div和最後4個帶有＃標籤的帖子（ft = 3）在另一個div。

Answer 1

您可以使用UNION運算符來做到這一點。

SELECT 
    'General' AS post_type, 
    id, 
    id_author, 
    content, 
    date, 
    ft 
FROM 
    Post 
WHERE 
    id_author = '$author' 
ORDER BY 
    id DESC 
LIMIT 7 
UNION ALL 
SELECT 
    'Image' AS post_type, 
    id, 
    id_author, 
    content, 
    date, 
    ft 
FROM 
    Post 
WHERE 
    id_author = '$author' AND 
    ft = 1 
ORDER BY 
    id DESC 
LIMIT 4 
UNION ALL 
SELECT 
    'Mentions' AS post_type, 
    id, 
    id_author, 
    content, 
    date, 
    ft 
FROM 
    Post 
WHERE 
    id_author = '$author' AND 
    ft = 2 
ORDER BY 
    id DESC 
LIMIT 4 
UNION ALL 
SELECT 
    'Hashtags' AS post_type, 
    id, 
    id_author, 
    content, 
    date, 
    ft 
FROM 
    Post 
WHERE 
    id_author = '$author' AND 
    ft = 3 
ORDER BY 
    id DESC 
LIMIT 4