Php 要删除数据库n中的名称,必须显示该名称是否存在
Php 要删除数据库n中的名称,必须显示该名称是否存在,php,pdo,Php,Pdo,$student\u name在您的代码中未定义,以检查受我们使用的上一条SQL语句影响的行数 <?php $hostname = "localhost"; $username = "ODBC"; $password = ""; $dbname = "db_students"; try{ $dbh = new PDO("mysql:host=$hostname;dbname=$dbname",$username,$passwo
$student\u name
在您的代码中未定义,以检查受我们使用的上一条SQL语句影响的行数
<?php
$hostname = "localhost";
$username = "ODBC";
$password = "";
$dbname = "db_students";
try{
$dbh = new PDO("mysql:host=$hostname;dbname=$dbname",$username,$password);
echo"Connected to database"."<br/>";
$dbh->setAttribute(PDO::ATTR_ERRMODE,PDO::ERRMODE_EXCEPTION);
$stmt = $dbh->prepare("DELETE FROM enrolments
WHERE student_name = :name");
$stmt->bindParam(":name",$name,PDO::PARAM_STR,255);
$name = "Pietie Kock";
$stmt->execute();
if($student_name > 0)
{
echo "record deleted ". $student_name;
}else{
echo "record doesn't exist". $student_name;
$dbh = null;
}catch(PDOException $e){
echo $e->getMessage();
}
?>
您还忘了关闭try
您的代码将被删除
$stmt->execute();
if ($stmt->rowCount > 0) {
echo "record deleted " . $student_name;
} else {
echo "record doesn't exist" . $student_name;
$dbh = null;
}
试试看{
$dbh=newpdo(“mysql:host=$hostname;dbname=$dbname”,$username,$password);
echo“已连接到数据库”。
;
$dbh->setAttribute(PDO::ATTR_ERRMODE,PDO::ERRMODE_异常);
$stmt=$dbh->prepare(“从注册中删除
其中学生姓名=:姓名“);
$stmt->bindParam(“:name”,$name,PDO::PARAM_STR,255);
$name=“Pietie Kock”;
$stmt->execute();
如果($stmt->rowCount>0){
回显“记录已删除”。$student\u姓名;
}否则{
echo“记录不存在”。$student\u name;
$dbh=null;
}
}catch(PDOException$e){//关闭您的尝试
echo$e->getMessage();
}
您应该至少添加一个问题,以及一些问题描述。请立即更改其格式,我下次上传问题时会这样做
try {
$dbh = new PDO("mysql:host=$hostname;dbname=$dbname", $username, $password);
echo"Connected to database" . "<br/>";
$dbh->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
$stmt = $dbh->prepare("DELETE FROM enrolments
WHERE student_name = :name");
$stmt->bindParam(":name", $name, PDO::PARAM_STR, 255);
$name = "Pietie Kock";
$stmt->execute();
if ($stmt->rowCount > 0) {
echo "record deleted " . $student_name;
} else {
echo "record doesn't exist" . $student_name;
$dbh = null;
}
} catch (PDOException $e) {// close you try
echo $e->getMessage();
}