search
HomeBackend DevelopmentPHP TutorialPHP MySql add, delete, modify, check, phpmysql add, delete, modify_PHP tutorial

PHP MySql add, delete, modify, check, phpmysql add, delete, modify

mysql_connect() connects to the database

mysql_select_db select database

mysql_fetch_assoc() gets the result set

mysql_query() executes sql statement

Examples are as follows:

$con=@mysql_connect('localhost','root','root');//Connect to the database
mysql_select_db('test',$con );//Select database
$userInfo=mysql_query("select * from user",$con);//Create sql statement
echo "

";
while($row=mysql_fetch_assoc ($userInfo))//Get the data for each row of the result set
{
echo "";
echo ""; ;/td>";
              echo "
";
echo $row['id' ];//Get the id in the row
          echo "
"; ;";
}
echo "
";
mysql_free_result($userInfo);//Release the result set
mysql_close($con); //Close the database
/ *delete
$d=@mysql_connect('localhost','root','root');
mysql_select_db('test',$d);
mysql_query("delete from user where id=1 ",$d);
mysql_close($d);
*/
/*insert
$i=@mysql_connect('localhost','root','root');
mysql_select_db('test',$i);
mysql_query("insert into user(username,password) values('ad','ad')",$i);
mysql_close($i);
*/
//update
$u=@mysql_connect('localhost','root','root');
mysql_select_db('test',$u);
mysql_query ("update user set username='aaa' where username='00'",$u);
echo "update user set username='ax' where id=2";
mysql_close($u);

?>


Thank you for your support!

You can contact me for communication. Renhanlinbsl@163.com Technorati Tags: PHP, Mysql, CRUD

http://www.bkjia.com/PHPjc/1135474.html

www.bkjia.com

true

TechArticlePHP MySql addition, deletion and modification query, phpmysql addition, deletion and modification mysql_connect() connects to the database mysql_select_db selects the database mysql_fetch_assoc() gets the result set mysql_query () Examples of executing sql statements are as follows:...
Statement
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
How can you check if a PHP session has already started?How can you check if a PHP session has already started?Apr 30, 2025 am 12:20 AM

In PHP, you can use session_status() or session_id() to check whether the session has started. 1) Use the session_status() function. If PHP_SESSION_ACTIVE is returned, the session has been started. 2) Use the session_id() function, if a non-empty string is returned, the session has been started. Both methods can effectively check the session state, and choosing which method to use depends on the PHP version and personal preferences.

Describe a scenario where using sessions is essential in a web application.Describe a scenario where using sessions is essential in a web application.Apr 30, 2025 am 12:16 AM

Sessionsarevitalinwebapplications,especiallyfore-commerceplatforms.Theymaintainuserdataacrossrequests,crucialforshoppingcarts,authentication,andpersonalization.InFlask,sessionscanbeimplementedusingsimplecodetomanageuserloginsanddatapersistence.

How can you manage concurrent session access in PHP?How can you manage concurrent session access in PHP?Apr 30, 2025 am 12:11 AM

Managing concurrent session access in PHP can be done by the following methods: 1. Use the database to store session data, 2. Use Redis or Memcached, 3. Implement a session locking strategy. These methods help ensure data consistency and improve concurrency performance.

What are the limitations of using PHP sessions?What are the limitations of using PHP sessions?Apr 30, 2025 am 12:04 AM

PHPsessionshaveseverallimitations:1)Storageconstraintscanleadtoperformanceissues;2)Securityvulnerabilitieslikesessionfixationattacksexist;3)Scalabilityischallengingduetoserver-specificstorage;4)Sessionexpirationmanagementcanbeproblematic;5)Datapersis

Explain how load balancing affects session management and how to address it.Explain how load balancing affects session management and how to address it.Apr 29, 2025 am 12:42 AM

Load balancing affects session management, but can be resolved with session replication, session stickiness, and centralized session storage. 1. Session Replication Copy session data between servers. 2. Session stickiness directs user requests to the same server. 3. Centralized session storage uses independent servers such as Redis to store session data to ensure data sharing.

Explain the concept of session locking.Explain the concept of session locking.Apr 29, 2025 am 12:39 AM

Sessionlockingisatechniqueusedtoensureauser'ssessionremainsexclusivetooneuseratatime.Itiscrucialforpreventingdatacorruptionandsecuritybreachesinmulti-userapplications.Sessionlockingisimplementedusingserver-sidelockingmechanisms,suchasReentrantLockinJ

Are there any alternatives to PHP sessions?Are there any alternatives to PHP sessions?Apr 29, 2025 am 12:36 AM

Alternatives to PHP sessions include Cookies, Token-based Authentication, Database-based Sessions, and Redis/Memcached. 1.Cookies manage sessions by storing data on the client, which is simple but low in security. 2.Token-based Authentication uses tokens to verify users, which is highly secure but requires additional logic. 3.Database-basedSessions stores data in the database, which has good scalability but may affect performance. 4. Redis/Memcached uses distributed cache to improve performance and scalability, but requires additional matching

Define the term 'session hijacking' in the context of PHP.Define the term 'session hijacking' in the context of PHP.Apr 29, 2025 am 12:33 AM

Sessionhijacking refers to an attacker impersonating a user by obtaining the user's sessionID. Prevention methods include: 1) encrypting communication using HTTPS; 2) verifying the source of the sessionID; 3) using a secure sessionID generation algorithm; 4) regularly updating the sessionID.

See all articles

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

WebStorm Mac version

WebStorm Mac version

Useful JavaScript development tools