Success code:

The table statement is as follows:

CREATE TABLE `kui3` (

`id` int(32) NOT NULL AUTO_INCREMENT ,

`username` varchar(30) DEFAULT NULL,

`password` varchar(32) DEFAULT NULL,

`createtime` int(80) DEFAULT NULL,

`createip` varchar(60) DEFAULT NULL,

PRIMARY KEY (`id`)

) ENGINE=InnoDB AUTO_INCREMENT=14 DEFAULT CHARSET=utf8 |

The complete code of the connect.php file is as follows:

##<?php

if (trim ($_POST['password']) != trim($_POST['repassword'])) {

exit('The two passwords are inconsistent, please return to the previous page');

}

$username = trim($_POST['username']);

$password = md5(trim($_POST['password']));

$time = time();

$ip = $_SERVER["REMOTE_ADDR"];

$conn = mysqli_connect('localhost', 'root', 'root');

//If there is an error, there is an error number

if (mysqli_errno($conn)) {

echo mysqli_error($conn);

exit;

}

mysqli_select_db($conn, 'kui');

mysqli_set_charset($conn, 'utf8');

$sql = "insert into kui3(username,password,createtime,createip) values('" . $username . "','" . $password . "','" . $time . "','" . $ip . "')" ;

$result = mysqli_query($conn, $sql);

if ($result) {

echo 'Success';

} else {

echo 'Failed';

}

echo 'The ID inserted by the current user is' . mysqli_insert_id($conn);

mysqli_close($ conn);

?>

CREATE TABLE IF NOT EXISTS user (

id int(11) NOT NULL,

username varchar(30) NOT NULL,

password char( 32) NOT NULL,

createtime int(11) NOT NULL,

createip int(11) DEFAULT NULL

) ENGINE=InnoDB DEFAULT CHARSET=utf8;

There are two questions here:

The first one should be, password varchar(32) not null;

The second and last createip type should be set to string,

The transfer is OK after modification

The ID inserted successfully by the current user is 13

String concatenation of SQL statements is incorrect

Do we need to create a table in the database first? That is to say, the table statement must be executed first before the connection can be successful:

CREATE TABLE `kui3` (

`id` int(32) NOT NULL AUTO_INCREMENT,

`username` varchar(30) DEFAULT NULL,

`password` varchar(32) DEFAULT NULL,

`createtime` int(80) DEFAULT NULL,

`createip` varchar( 60) DEFAULT NULL,

PRIMARY KEY (`id`)

) ENGINE=InnoDB AUTO_INCREMENT=14 DEFAULT CHARSET=utf8 |

Yes?

`createtime` int(80) DEFAULT NULL, isn’t this int(80) a bit scary? And you can use the date type of the database

Then when inserting, enclose the time in quotation marks, because the time is stored in the form of a string, both $time and ip in your question should be enclosed in parentheses