我有一个SQL查询应该从我的学生表中获取程序,类和年份,给出两列X和Y数字.例如,如果x = 3且Y = 4,则表示学生3和4之间存在连接,为了我们的论证,我将从学生4中选择程序,班级,年份.
问题是,如果有两行,其中X和Y相等,例如:第1行:X = 3,Y = 4第2行:X = 3,Y = 4
(因为可能有两个连接),SELECT只会选择程序,类和年只是ONCE,而不是两次.我希望它能单独选择重复,所以我的循环稍后会回显两次.
我希望自己清楚明白!
$SQL = "
SELECT Programme, Class, Year
FROM Students
WHERE Student_ID in (
SELECT X
FROM SearchStudent
WHERE Y= '$id'
)";
Run Code Online (Sandbox Code Playgroud) 这是我用来显示页面的COUNT查询:
$sql = "
SELECT SUM(num) as num FROM (
SELECT
COUNT(URL) AS num
, 'World' AS GoSection
, 'GW' AS MySite
FROM gw_geog
WHERE URL = :MyURL AND G1 = 1
UNION ALL
SELECT
COUNT(URL) AS num
, 'World' AS GoSection
, 'GW' AS MySite
FROM gw_geog_political
WHERE URL = :MyURL
) AS X";
$stmt = $pdo->prepare($sql);
$stmt->bindParam(':MyURL',$MyURL,PDO::PARAM_STR);
$stmt->execute();
$Total = $stmt->fetch();
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我想做两个改变:
1)从每行删除WHERE URL =:MyURL,并将其合并到查询末尾的单行中
2)通过添加LIMIT 1来重复Zap
这就是我现在正在使用的.
$sql = "SELECT SUM(num) as num …Run Code Online (Sandbox Code Playgroud) 我试图根据其键创建嵌套数组.如果简化任务,也可以更改原始数组中的键格式.
来自:
$arr = [
'player.name' => 'Joe',
'player.lastName' => 'Snow',
'team.name' => 'Stars',
'team.picture.name' => 'Joe Snow Profile',
'team.picture.file' => 'xxx.jpg'
];
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至:
$arr = [
'player' => [
'name' => 'Joe'
, 'lastName' => 'Snow'
]
,'team' => [
'name'=> 'Stars'
,'picture' => [
'name' => 'Joe Snow Profile'
, 'file' =>'xxx.jpg'
]
],
];
Run Code Online (Sandbox Code Playgroud) 第一页有两个超链接:
<p> COE <a href="page2.php">here</a></p>
<p> SWE <a href="page2.php">here</a></p>
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我想要的是:当用户点击第一个链接时,page2应该显示以下链接:
<p> academic transcript <a href="A.php">here</a></p>
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当用户点击第二个链接时,page2将显示不同的链接,即:
<p> courses list <a href="B.php">here</a></p>
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我能这样做吗?