The main content of this article is about PDO querying one row of data at a time, which has certain reference value. Now I share it with everyone. Friends in need can refer to it
<?php require 'pdo_edu_config.php'; try{ $pdo=new PDO($dsn,$userName,$passWord); $sql="SELECT id,name,course,grade FROM student WHERE grade>70"; $result=$pdo->query($sql);//返回一个PDOstatement结果集对象 if($result && $result->rowCount()){//判断结果集对象是否存在,并且结果集数量是否大于0,也就是说是否存在数据 //rowCount()是结果集中的一个方法,可以返回当前结果集中的记录条数 $result->setFetchMode(PDO::FETCH_ASSOC);//设置结果集的读取方式,这里用的是关联的方式进行读取 $row=$result->fetch();//获取记录 print_r($row); } }catch(PDOException $e){ die($e->getMessage()); }
You can use $result->rowCount>0 to determine whether the data has been queried, which can be used for query judgment when the user logs in.
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PHP database is based on PDO operation Class(mysql)
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