【发布时间】：2015-05-17 02:00:01
【问题描述】：
我有多个表都具有相似的基本结构：
biopsy_p0
id | biopsy_id | introduced
biopsy_p1
id | biopsy_p0_id | introduced
biopsy_p2
id | biopsy_p1_id | introduced
我的目标是获得一个依赖关系的树形视图
biopsy_p0.id->biopsy_p1.biopsy_p0_id->biopsy_p2.biopsy_p1_id
我试图只用 SQL 来做，但正如你从我的问题中看到的那样，我在这方面不是很有经验。到目前为止，我能找到的所有内容都是关于分层树的参考资料。但是那些总是只使用一个带有内部引用的表。
--- 更新： 我现在让它与 PHP 一起工作，它真的不是一个很好的解决方案，我希望我可以用 SQL 来实现它，这样扩展起来会更好一些：
PHP 代码：
$database = DatabaseFactory::getFactory()->getConnection();
// Get all p0 element asociated with the biopsy
$sql = "SELECT *
FROM biopsy_p0
WHERE biopsy_id = :id";
$query = $database->prepare($sql);
$query->execute(array(':id' => $id));
$p0 = $query->fetchAll();
// Get all p1 elements
$sql="SELECT *
FROM biopsy_p0 as p0
RIGHT JOIN biopsy_p1 as p1
ON p0.id=p1.biopsy_p0_id
WHERE biopsy_id = :id;";
$query = $database->prepare($sql);
$query->execute(array(':id' => $id));
$p1 = $query->fetchAll();
for ($i=0; $i < count($p0); $i++)
{
$p1Array = new ArrayObject();
foreach ($p1 as $key => $value)
{
if ($value->biopsy_p0_id == $p0[$i]->id)
{
$p1Array->append($value);
}
$p0[$i]->p1 = $p1Array;
}
unset($p1Array);
}
if ($p0 != NULL){
return $p0;
}
return FALSE;
结果： 这正是我所需要的，但是 PHP 很混乱，而且它的复杂性随着我想检查的每个子级别而增加。
details: Array
(
[0] => stdClass Object
(
[id] => 1
[biopsy_id] => 226
[introduced] => 2014-12-31
[p1] => ArrayObject Object
(
[storage:ArrayObject:private] => Array
(
[0] => stdClass Object
(
[id] => 1
[biopsy_id] => 226
[introduced] => 2015-03-18
[biopsy_p0_id] => 1
)
[1] => stdClass Object
(
[id] => 3
[biopsy_id] => 226
[introduced] => 2015-03-17
[biopsy_p0_id] => 1
)
[2] => stdClass Object
(
[id] => 4
[biopsy_id] => 226
[introduced] => 2015-03-18
[biopsy_p0_id] => 1
)
)
)
)
[1] => stdClass Object
(
[id] => 2
[biopsy_id] => 226
[introduced] => 2014-12-31
[p1] => ArrayObject Object
(
[storage:ArrayObject:private] => Array
(
[0] => stdClass Object
(
[id] => 2
[biopsy_id] => 226
[introduced] => 2015-03-31
[biopsy_p0_id] => 2
)
[1] => stdClass Object
(
[id] => 6
[biopsy_id] => 226
[introduced] => 2015-03-01
[biopsy_p0_id] => 2
)
)
)
)
[2] => stdClass Object
(
[id] => 3
[biopsy_id] => 226
[introduced] => 2014-12-31
[p1] => ArrayObject Object
(
[storage:ArrayObject:private] => Array
(
[0] => stdClass Object
(
[id] => 5
[biopsy_id] => 226
[introduced] => 2015-03-11
[biopsy_p0_id] => 3
)
)
)
)
)
SQL 数据：
CREATE TABLE IF NOT EXISTS `biopsy` (
`id` int(11) unsigned NOT NULL,
`creation_date` date NOT NULL
) ENGINE=InnoDB AUTO_INCREMENT=228 DEFAULT CHARSET=latin1;
INSERT INTO `biopsy` (`id`, `creation_date`) VALUES
(226, '2015-03-08'),
(227, '2015-03-08');
CREATE TABLE IF NOT EXISTS `biopsy_p0` (
`id` int(11) unsigned NOT NULL,
`biopsy_id` int(11) unsigned NOT NULL,
`introduced` date NOT NULL
) ENGINE=InnoDB AUTO_INCREMENT=7 DEFAULT CHARSET=latin1;
INSERT INTO `biopsy_p0` (`id`, `biopsy_id`, `introduced`) VALUES
(1, 226, '2014-12-31'),
(2, 226, '2014-12-31'),
(3, 226, '2014-12-31'),
(4, 227, '2015-03-14'),
(5, 255, '2015-03-10'),
(6, 255, '2015-03-12');
CREATE TABLE IF NOT EXISTS `biopsy_p1` (
`id` int(11) unsigned NOT NULL,
`biopsy_p0_id` int(11) unsigned NOT NULL,
`introduced` date NOT NULL
) ENGINE=InnoDB AUTO_INCREMENT=7 DEFAULT CHARSET=latin1;
INSERT INTO `biopsy_p1` (`id`, `biopsy_p0_id`, `introduced`) VALUES
(1, 1, '2015-03-18'),
(2, 2, '2015-03-31'),
(3, 1, '2015-03-17'),
(4, 1, '2015-03-18'),
(5, 3, '2015-03-11'),
(6, 2, '2015-03-01');
也许最好有一个层次关系表，通过 ID 引用另一个存储实际数据的表...这样我只涉及两个表，如果添加新元素会更灵活...
【问题讨论】：
-
将
RIGHT JOIN更改为LEFT JOIN -
感谢您的回复。我已经尝试过了，但它也只给了我尾注。所以只有 - 第二级 A - 第二级 B 等等。
-
您能否提供说明问题的示例数据（创建表和插入语句）？
-
我现在为这个问题添加了一个 PHP 解决方案。但这真的不太好，所以如果有任何想法我可以如何使用 SQL 来管理它，我将不胜感激。
-
查看我之前的评论
标签： php sql treeview hierarchical