Question

当我在数据库中执行sql查询时，我有一个内部联接工作我想要它。

SELECT debate.date, school1.name, school2.name
FROM debate
INNER JOIN schools as school1
ON debate.homeid=school1.id
INNER JOIN schools as school2
ON debate.awayid=school2.id

返回

date        name        name
19-01-2013  st Peters   St Simons

当我尝试使用php时这样做。我使用相同的select语句并在下面添加。

foreach ($result as $row)
{
  $debates[] = array(
    'date' => $row['date'],
    'awayschool' => $row['name'],
    'homeschool' => $row['name'],
  );
}


<table>
<tr>
<td><?php echo $debate['date']; ?></td>
<td><?php echo $debate['name']; ?></td>
<td><?php echo $debate['name']; ?></td>
</tr>
</table>

返回

date        name        name
19-01-2013  st Peters   st Peters

但是我希望它能够回归。

date        name        name
19-01-2013  st Peters   St Simons

在我的数组中，我尝试了几种不同的东西，比如替换

'awayschool' => $row['name'],

与

'awayschool' => $row['school1.name'],

但是当我这样做时，我收到一个错误，指出未定义的索引。

我在这里做错了什么？

Answer 1

这里的问题是school1.name和school2.name都是（在php中）都命名为$ row ['name']，你可以使用AS获取一个来重命名它

SELECT debate.date, school1.name, school2.name AS name2
FROM debate
INNER JOIN schools as school1
ON debate.homeid=school1.id
INNER JOIN schools as school2
ON debate.awayid=school2.id

然后将你的foreach循环改为

foreach ($result as $row)
{
  $debates[] = array(
    'date' => $row['date'],
    'awayschool' => $row['name'],
    'homeschool' => $row['name2'],
  );
}

Answer 2

像这样修改您的查询

SELECT debate.date, school1.name "School1Name", school2.name "School2Name"
FROM debate
INNER JOIN schools as school1
ON debate.homeid=school1.id
INNER JOIN schools as school2
ON debate.awayid=school2.id;

然后：

foreach ($result as $row)
{
  $debates[] = array(
    'date' => $row['date'],
    'awayschool' => $row['School1Name'],
    'homeschool' => $row['School2Name'],
  );
}

Answer 3

只需为他们使用别名。就像school1.name AS SCHLNAME1, school2.name AS SCHLNAME2 那么这些索引将在你的数组中可用。然后它将是

'awayschool' => $row['SCHLNAME1'],
'awayschool' => $row['SCHLNAME2']

Answer 4

尝试更改以下内容

<td><?php echo $debate['date']; ?></td>
<td><?php echo $debate['name']; ?></td>
<td><?php echo $debate['name']; ?></td>

到这个

 <td><?php echo $debate['date']; ?></td>
 <td><?php echo $debate['awayschool']; ?></td>
 <td><?php echo $debate['homeschool']; ?></td>

PHP数组选择内连接

4 个答案: