MySQL如何实现更新查询?
MySQL UPDATE查询用于更新MySQL数据库中表中的现有记录。它可以用于同时更新一个或多个字段。并且可用于使用WHERE子句指定任何条件。(相关推荐:《MySQL教程》)
UPDATE更新查询的基本语法是
Where Update查询的实现:
让我们考虑下表“Data”,其中包含四列“ID”,“FirstName”,“LastName”和“Age”。
要更新“Data”表中“ID”为201的人员的“Age”,我们可以使用以下代码:
使用过程方法更新查询:<?php$link = mysqli_connect("localhost", "root", "", "Mydb");if($link === false){die("ERROR: Could not connect. ". mysqli_connect_error()); }$sql = "UPDATE data SET Age='28' WHERE id=201"; if(mysqli_query($link, $sql)){echo "Record was updated successfully."; } else {echo "ERROR: Could not able to execute $sql. ". mysqli_error($link); }mysqli_close($link); ?>输出:更新后的表格
Web浏览器上的输出:
使用面向对象的方法更新查询:<?php$mysqli = new mysqli("localhost", "root", "", "Mydb");if($mysqli === false){die("ERROR: Could not connect. ". $mysqli->connect_error); }$sql = "UPDATE data SET Age='28' WHERE id=201"; if($mysqli->query($sql) === true){echo "Records was updated successfully."; } else{echo "ERROR: Could not able to execute $sql. ". $mysqli->error; } $mysqli->close(); ?>使用PDO方法更新查询:<?phptry{$pdo = new PDO("mysql:host=localhost;dbname=Mydb", "root", "");$pdo->setAttribute(PDO::ATTR_ERRMODE,PDO::ERRMODE_EXCEPTION); } catch(PDOException $e){die("ERROR: Could not connect. ". $e->getMessage()); }try{$sql = "UPDATE data SET Age='28' WHERE id=201";$pdo->exec($sql);echo "Records was updated successfully."; } catch(PDOException $e){die("ERROR: Could not able to execute $sql. ". $e->getMessage()); } unset($pdo); ?>本篇文章就是关于MySQL更新查询的介绍,希望对需要的朋友有所帮助!以上就是MySQL如何实现更新查询?的详细内容,更多请关注小潘博客其它相关文章!