Head First PHP&MySQL学习笔记(二)

三. 创建与填充数据库

1. Web应用是一个设计用来满足用户某个特定目标的动态网站

2. PHP代码中，SQL语句无需以分号结尾；而MySqL终端的每个SQL语句结尾都要加分号

3. 创建数据库：CREATE DATABASE database_name

    创建表：CREATE TABLE table_name(column_name1 column_type1,column_name2 column_type2,……)

    选择默认数据库：USE database_name

    展示表的结构：DESCRIBE table_name

    删除表：DROP TABLE table_name

    删除数据： DELETE FROM table_name

    配合where字句指定范围

4. 对于在MySQL中如何表示yes/no值可能还有异议，char(1)这种方法很直接也很高效

5. ->提示符，是标明你还在输入同一条语句，语句结束并加上分号后MySQL就会执行这条语句

6. mysqli_fetch_array()函数将一个数据行存储在一个数组中    

7. 代码示例

<?php // addemail.php

  $dbc = mysqli_connect(&#39;localhost&#39;, &#39;root&#39;, &#39;&#39;, &#39;elvis_store&#39;)
    or die(&#39;Error connecting to MySQL server.&#39;);

  $first_name = $_POST[&#39;firstname&#39;];  // 从前台获取数据
  $last_name = $_POST[&#39;lastname&#39;];
  $email = $_POST[&#39;email&#39;];

  $query = "INSERT INTO email_list (first_name, last_name, email)  VALUES (&#39;$first_name&#39;, &#39;$last_name&#39;, &#39;$email&#39;)";
  mysqli_query($dbc, $query)          // 执行SQL语句
    or die(&#39;Error querying database.&#39;);

  echo &#39;Customer added.&#39; . $email;

  mysqli_close($dbc);
?>

<pre name="code" class="php"><?php &#160;&#160;// sendemail.php

  $from = 'jarray@foxmail.com';
  $subject = $_POST['subject'];
  $text = $_POST['elvismail'];

  $dbc = mysqli_connect('localhost', 'root', '', 'elvis_store')
    or die('Error connecting to MySQL server.');

  $query = "SELECT * FROM email_list";
  $result = mysqli_query($dbc, $query)            // 执行SQL语句
    or die('Error querying database.');

  while ($row = mysqli_fetch_array($result)){     // while循环条件是mysqli_fetch_array()函数的返回值
    $to = $row['email'];
    $first_name = $row['first_name'];
    $last_name = $row['last_name'];
    $msg = "Dear $first_name $last_name,\n$text";
    mail($to, $subject, $msg, 'From:' . $from);
    echo 'Email sent to: ' . $to . '<br>';
  } 

  mysqli_close($dbc);
?>

<?php // removeemail.php
&#160; 
&#160; $dbc = mysqli_connect(&#39;localhost&#39;, &#39;root&#39;, &#39;&#39;, &#39;elvis_store&#39;)
    or die(&#39;Error connecting to MySQL server.&#39;);

  $email = $_POST[&#39;email&#39;];

  $query = "DELETE FROM email_list WHERE email = &#39;$email&#39;";   // 删除数据库中指定条件的邮件
  mysqli_query($dbc, $query)
    or die(&#39;Error querying database.&#39;);

  echo &#39;Customer removed: &#39; . $email;

  mysqli_close($dbc);
?>

以上就介绍了Head First PHP&MySQL学习笔记(二)，包括了方面的内容，希望对PHP教程有兴趣的朋友有所帮助。