與PHP和MySQL的分頁關系

Question

我想顯示數據庫表中的6條記錄。 2個表之間存在一對多關系。 使用自定義映射器，我將這些記錄映射如下。

$result  = [
   0=>[
        "name"=>"jithin",
        "phone"=>"907856",
        "messages"=>[
                      0=>[
                          "title"=>"text messgae"
                         ],
                      1=>[
                          "title"=>"Data messgae"
                         ]
                    ]
      ],
    1=>[
        "name"=>"Rijin",
        "phone"=>"90247856",
        "messages"=>[
                      0=>[
                          "title"=>"text messgae"
                         ],
                      1=>[
                          "title"=>"Data messgae"
                         ]
                    ]
      ]
]

QUERY

"SELECT u.* , m.* FROM user u INNER JOIN messages m ON m.userId = u.id
 WHERE m.date BETWEEN "12-12-2015" AND "12-12-2018" LIMIT 0, 6; 

該查詢將返回如下數據

userId | name | messages|
-------|------|---------|
1      |jithin| hai     |
1      |jithin| hello   |
1      |jithin| Why?    |
2      |Rijin | hai     |
2      |Rijin | Where   |
2      |Rijin | Why?    |
------------------------- 

但是我需要另外4個人的另外4條記錄。 我正在使用php和mysql5.7。

Answer 1

如果我了解您的需求：

    SELECT u.id, u.userName , m.message
    FROM user u 
    INNER JOIN messages m ON m.userId = u.id
    INNER JOIN (SELECT u.id as user_id FROM user u LIMIT 0, 6) as users
        ON users.user_id = u.id
    WHERE m.date BETWEEN '12-12-2015' AND '12-12-2018';

Answer 2

最后，我找到了這個問題的答案。

"SELECT u.* , m.* FROM user u 
 INNER JOIN messages m ON m.userId = u.id
 INNER JOIN (SELECT DISTINCT u.id as user_id FROM user u 
             INNER JOIN messages m ON m.userId = u.id
             WHERE m.date BETWEEN "12-12-2015" 
             AND "12-12-2018" LIMIT 0, 6) 
 AS distinct_users ON distinct_users.user_id=u.id
 WHERE m.date BETWEEN "12-12-2015" AND "12-12-2018"; 

這將返回准確的6個人消息，我們可以輕松管理分頁。 如果您還有另一個簡單的選擇。 請在這里發布。