First create a database about books, named book.
<?php
// 创建连接
$conn = new mysqli("localhost", "uesename", "password");
// 检测连接
if ($conn->connect_error)
{
die("连接失败: " . $conn->connect_error);}
// 创建数据库
$sql = "CREATE DATABASE book";
if ($conn->query($sql) === TRUE)
{
echo "数据库创建成功";
} else {
echo "Error creating database: " . $conn->error;
}
$conn->close();
?>Create an administrator table in the database, named admin
Set the following fields:
id: It is unique, of type int, and selects the primary key.
username: Administrator name, type is varchar, length is 50.
password: Password, type is varchar, length is 50.
<?php
$SQL = " CREATE TABLE IF NOT EXISTS `admin` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`username` varchar(50) CHARACTER SET utf8 DEFAULT NULL,
`password` varchar(50) CHARACTER SET utf8 DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_bin AUTO_INCREMENT=2 ";
?>
Here we need to continue to use the yx_book table of "PHP to develop a simple book lending system"
The fields are as follows:
id: It is unique, type is int, and Select the primary key.
name: Book name, type is varchar, length is 20.
price: Price, type decimal(4,2), used for data storage with relatively high precision.
The declaration syntax of decimal column is decimal(m,d).
1. M is the maximum number of numbers (precision). Its range is 1 to 65 (in older MySQL versions, the allowed range was 1 to 254).
2. D is the number of digits to the right of the decimal point (scale). Its range is 0~30, but it must not exceed M.
uploadtime: storage time, type is datetime.
type: Book classification, type is varchar, length is 10.
total: Number of books, type is int, length is 50.
leave_number: The number of remaining books that can be borrowed, type is int, length is 10.
<?php
$SQL = " CREATE TABLE IF NOT EXISTS `yx_books` (
`id` int(10) NOT NULL AUTO_INCREMENT,
`name` varchar(20) CHARACTER SET utf8 NOT NULL,
`price` decimal(4,2) NOT NULL,
`uploadtime` datetime NOT NULL,
`type` varchar(10) CHARACTER SET utf8 NOT NULL,
`total` int(50) DEFAULT NULL,
`leave_number` int(10) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=MyISAM DEFAULT CHARSET=utf8 COLLATE=utf8_bin AUTO_INCREMENT=42 ";
?>
Write the created database table into the config.php file so that we can call the database table on different pages in the future.
<?php
ob_start();
session_start(); //开启缓存
header("Content-type:text/html;charset=utf-8");
$link = mysqli_connect('localhost','username','password','book');
mysqli_set_charset($link, "utf8");
if (!$link) {
die("连接失败:".mysqli_connect_error());
}
?>Next Section