php - MYSQL 在 mysql_query 数组中定义特定的列？

Question

当我从共享列名的多个表中进行选择时，有没有一种方法可以同时返回这两个表，但定义我想从哪个表中选择数据？

例如:这两个表都包含“日期”列，我想同时使用它们，但我想避免重命名每个具有重复名称的列。

 $query = mysql_query("SELECT * FROM posts, comments"); //(SELECT * is just for example)
 while($row=mysql_fetch_array($query))
 {
     $postDate = $row['date'];  //I would like to be able to do something like:
                                //$postDate = $row['posts']['date']; OR $row['posts.date'];
                                //of course it's all in an array now, jumbled up.
     $commentDate = $row['date']; 
 }

Answer 1

如果您需要，您需要在查询中为重复的列名添加别名，例如

SELECT p.date AS postDate, c.date AS commentDate
FROM posts p, comments c

然后使用别名检索值

$postDate = $row['postDate'];
$commentDate = $row['commentDate'];

仅供引用，SELECT * 几乎不是一个好主意，尤其是 涉及多个表时。您应该始终尝试具体说明添加到 SELECT 子句

中的列