<?php //数据库连接 $conn = mysql_connect('localhost', 'root', ''); mysql_select_db('test', $conn); mysql_query("SET NAMES GBK"); /* 支持事务的表必须是InnoDB类型 一段事务中只能出现一次: mysql_query('START TRANSACTION');//开始事务 mysql_query(' ROLLBACK ');//回滚事务 mysql_query('COMMIT');//提交事务 如果一段事务中出现多次回滚事务,则在,提交事务时只将第一次回滚前至开始事务后对数据库的所有操作取消,第一次回滚后至提交事务前所有对数据库操作仍将有效,所以一般将回滚语句仅放在提交事务语句前 如果一段事务无提交语句,则从开始事务时以下的所有对数据库操作虽执行(执行方法返回对错),但对数据库无影响,但是在执行下段开始事务语句时,前段事务自动提交 */ mysql_query('START TRANSACTION'); $isBad = 0; $ins_testTable1 = "INSERT INTO testtable1(NAME,age)VALUES('first',23)"; if(!mysql_query($ins_testTable1)){ $isBad =1; } //插入语句字段名有错 $ins_testTable2 = "INSERT INTO testtable1(NAME,ages)VALUES('second','24')"; if(!mysql_query($ins_testTable2)){ $isBad =1; } if($isBad == 1){ echo $isBad; mysql_query('ROLLBACK '); } mysql_query('COMMIT'); mysql_close($conn); ?>

PHPsessionscanstorestrings,numbers,arrays,andobjects.1.Strings:textdatalikeusernames.2.Numbers:integersorfloatsforcounters.3.Arrays:listslikeshoppingcarts.4.Objects:complexstructuresthatareserialized.

TostartaPHPsession,usesession_start()atthescript'sbeginning.1)Placeitbeforeanyoutputtosetthesessioncookie.2)Usesessionsforuserdatalikeloginstatusorshoppingcarts.3)RegeneratesessionIDstopreventfixationattacks.4)Considerusingadatabaseforsessionstoragei

Session regeneration refers to generating a new session ID and invalidating the old ID when the user performs sensitive operations in case of session fixed attacks. The implementation steps include: 1. Detect sensitive operations, 2. Generate new session ID, 3. Destroy old session ID, 4. Update user-side session information.

PHP sessions have a significant impact on application performance. Optimization methods include: 1. Use a database to store session data to improve response speed; 2. Reduce the use of session data and only store necessary information; 3. Use a non-blocking session processor to improve concurrency capabilities; 4. Adjust the session expiration time to balance user experience and server burden; 5. Use persistent sessions to reduce the number of data read and write times.

PHPsessionsareserver-side,whilecookiesareclient-side.1)Sessionsstoredataontheserver,aremoresecure,andhandlelargerdata.2)Cookiesstoredataontheclient,arelesssecure,andlimitedinsize.Usesessionsforsensitivedataandcookiesfornon-sensitive,client-sidedata.

PHPidentifiesauser'ssessionusingsessioncookiesandsessionIDs.1)Whensession_start()iscalled,PHPgeneratesauniquesessionIDstoredinacookienamedPHPSESSIDontheuser'sbrowser.2)ThisIDallowsPHPtoretrievesessiondatafromtheserver.

The security of PHP sessions can be achieved through the following measures: 1. Use session_regenerate_id() to regenerate the session ID when the user logs in or is an important operation. 2. Encrypt the transmission session ID through the HTTPS protocol. 3. Use session_save_path() to specify the secure directory to store session data and set permissions correctly.

PHPsessionfilesarestoredinthedirectoryspecifiedbysession.save_path,typically/tmponUnix-likesystemsorC:\Windows\TemponWindows.Tocustomizethis:1)Usesession_save_path()tosetacustomdirectory,ensuringit'swritable;2)Verifythecustomdirectoryexistsandiswrita


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

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

Hot Article

Hot Tools

SublimeText3 Linux new version
SublimeText3 Linux latest version

SublimeText3 Chinese version
Chinese version, very easy to use

Dreamweaver CS6
Visual web development tools

EditPlus Chinese cracked version
Small size, syntax highlighting, does not support code prompt function

WebStorm Mac version
Useful JavaScript development tools
