php - 修改查询以获取请求的值

Question

请我在这里有这个查询，我用它来从数据库中提取一些行。

$rs = mysql_query("SELECT u.*, SUM(c.ts) AS total_sum1, SUM(m.bv) AS total_sum 
FROM users u 
LEFT JOIN 
 (SELECT user_id ,SUM(points) AS ts FROM coupon GROUP BY user_id) c 
 ON   u.user_id like'%$search%'
LEFT JOIN 
 (SELECT user_id ,SUM(points) AS bv FROM matching GROUP BY user_id) m 
ON u.user_id=m.user_id 

GROUP BY u.user_id limit $offset,$rows");

我需要对其进行修改，使其仅查询满足此条件的行：

u.user_id like '%$search%'

我应该把上述条件放在哪里？我尝试添加一个 AND 运算符，但它仍然不会给出一行，因为 user_id 彼此不同。

谢谢

Answer 1

你可以试试这个 SQL。（我不懂 PHP）

SELECT 
       u.*, 
       SUM(c.points) AS total_sum1, 
       SUM(m.points) AS total_sum 
FROM users u 

INNER JOIN coupon c  ON   u.user_id=m.user_id 
INNER JOIN matching  m  ON u.user_id=m.user_id 

WHERE u.user_id like '%$search%'
GROUP BY u.user_id limit $offset,$rows" ;

Answer 2

您需要添加一个WHERE子句才能添加该条件：

$rs = mysql_query("SELECT u.*, SUM(c.ts) AS total_sum1, SUM(m.bv) AS total_sum 
FROM users u 
LEFT JOIN 
 (SELECT user_id ,SUM(points) AS ts FROM coupon GROUP BY user_id) c 
 ON   u.user_id like'%$search%'
LEFT JOIN 
 (SELECT user_id ,SUM(points) AS bv FROM matching GROUP BY user_id) m 
ON u.user_id=m.user_id 
WHERE u.user_id like '%$search%'
GROUP BY u.user_id limit $offset,$rows");

旁注：

• 该mysql_*库已弃用，请考虑升级到现代 API，例如PDO或 MySQLi
• 使用带有绑定参数的预处理语句优于将变量连接到 SQL 中。Prepared Statements 更加安全且易于使用，因为您不必担心转义。