PHP+MySQL

链接和关闭

创建数据库&创建表

执行完成-数据库关闭";

?>

MySQL数据类型

4D134F37-DC97-4744-ABE2-CD6267B3DA6E.png

插入数据

执行完成-数据库关闭";

?>

使用表单插入数据

post.php

Firstname: 
Lastname: 
Age: 

dbtest.php

";
    }
    //create table in my_db database
    mysql_select_db("my_db",$con);
    
    $sql = "INSERT INTO Person (FirstName,LastName,Age) 
        VALUES ('$_POST[firstname]','$_POST[lastname]','$_POST[age]')";
    if (!mysql_query($sql,$con)) {
        # code...
        die('Error:'.mysql_error());
    }
    echo "添加了一条数据";
    mysql_close($con);
    echo "
执行完成-数据库关闭";

?>

查询

";
    }
    // table in my_db database
    mysql_select_db("my_db",$con);
    
    $result = mysql_query("SELECT * FROM Person");

    while ($row = mysql_fetch_array($result)) {
        # code...
        echo "姓名:".$row['FirstName']."   ".$row['LastName'];
        echo "
";
    }

    mysql_close($con);
    echo "
执行完成-数据库关闭";

?>

条件查询

运算符

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$result = mysql_query("SELECT * FROM Person WHERE FirstName = 'aaaaa' ");

排序

默认升序

$result = mysql_query("SELECT * FROM Persons ORDER BY age");

使用 DESC 关键词来设定降序排序（9 在 1 之前，"p" 在 "a" 之前）：

SELECT column_name(s)
FROM table_name
ORDER BY column_name DESC

可以根据多个列进行排序。当按照多个列进行排序时，只有第一列相同时才使用第二列：

SELECT column_name(s)
FROM table_name
ORDER BY column_name1, column_name2

更新数据

UPDATE table_name
SET column_name = new_value
WHERE column_name = some_value

$sql = mysql_query("UPDATE Person SET Age = '100' WHERE FirstName = 'aaaaa'");

删除数据

DELETE FROM table_name
WHERE column_name = some_value

$sql = mysql_query("DELETE FROM Person WHERE FirstName = '11'");