我如何按技能对其进行分组并回显每项技能的所有照片。
SELECT skills.teacher, skills.student, skills.skill, profile.photo
FROM skills
INNER JOIN profile ON skills.student = profile.username
WHERE teacher = 'teach1'
teacher | student | skill | photo
------- | -------- | ------ | ------------
teach1 | student1 | skill1 | student1.jpg
teach1 | student2 | skill1 | student2.jpg
teach1 | student3 | skill2 | student3.jpg
teach1 | student3 | skill1 | student3.jpg
teach1 | student4 | skill3 | student4.jpg
teach1 | student1 | skill2 | student1.jpg
我强调这是一个例子。我实际上不知道“技能”的名称,因为它们是学生们创造的。不知道总共会列出多少技能。我不知道哪些用户会给哪些老师添加哪些技能。
我尝试过 while 循环和 foreach 循环。我只是不知道如何对其进行分组以及使用什么类型的循环...
我需要我的最终结果来让我 echo 。
<div>skill1
<img src="student1.jpg">
<img src="student2.jpg">
<img src="student3.jpg">
...
...
...
</div>
<div>skill2
<img src="student1.jpg">
<img src="student3.jpg">
...
...
...
</div>
<div>skill3
<img src="student4.jpg">
...
...
...
</div>
最佳答案
首先,按技能排序,以便按顺序排列它们:
SELECT skills.teacher, skills.student, skills.skill, profile.photo
FROM skills
INNER JOIN profile ON skills.student = profile.username
WHERE teacher = 'teach1'
ORDER BY skills.skill
在 while 循环之外分配一个变量(在本例中为 $lastSkill
)。检查它是否改变,并相应地输出内容。看看下面的例子。您的 PHP 代码看起来与此类似:
$lastSkill = null;
while ( $row = fetchrow() )
{
if ( $row['skill'] !== $lastSkill )
{
//Don't close a div, if it's the first row
if ( $lastSkill !== null )
echo '</div>';
//We've moved onto a new row, echo it out
echo '<div>' . $row['skill'];
//Store the lastSkill
$lastSkill = $row['skill'];
}
echo '<img src="' . $row['photo'] . '">';
}
关于PHP 分组和循环,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/38734202/