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Operating MongoDB database with PHP_PHP tutorial

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Jul 12, 2016 am 09:06 AM

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<p></p> <h2 id="PHP-operates-MongoDB-database">PHP operates MongoDB database</h2> <p> </p> <p> </p> <p><strong>1. Introduction to MongoDB</strong></p> <p>MongoDB (the name comes from "humongous") is a scalable, high-performance, open source, schema-free, document-oriented database that combines the advantages of document databases, key-value storage and relational databases. </p> <p><b> </b></p> <p><strong>MongoDB features: </strong></p> <p>• Document-oriented storage (JSON-like data schema is simple and powerful)<br> • Dynamic query<br> • Full index support, extended to internal objects and embedded arrays <br> • Query record analysis<br> • Fast, in-place updates <br> • Efficiently store binary large objects (such as photos and videos) <br> • Replication and failover support<br> • Auto-Sharding supports cloud-level scalability<br> • MapReduce supports complex aggregations <br> • Business support, training and consulting</p> <p> </p> <p><strong>2. Install MongoDB</strong></p> <p>Installing MongoDB is very simple, just download the compressed package, decompress it and run the command </p> <p><strong>Download address: </strong> https://www.mongodb.org/downloads</p> <p>This article is for Windows platform, MongoDB running command: >bin/mongod</p> <p>Tip: First create a folder to store data. MongoDB’s default data storage directory is /data/db/ (or c:datadb). Of course, you can also change it to a different directory by specifying the –dbpath parameter. </p> <p><strong> Example: </strong><br> >bin/mongod –dbpath=d:mgdatadb</p> <p>For more information, please refer to my CSDN blog: MongoDB installation configuration</p> <p> </p> <p><strong>3. Install MongoDB PHP extension </strong></p> <p>Download the PHP extension according to your PHP version: </p> <p>http://php.net/manual/en/mongo.installation.php#mongo.installation.nix<br> http://www.php.net/manual/en/mongo.installation.php#mongo.installation.windows</p> <p>Tips: <br> 1. VC6 is suitable for Apache and VC9 is suitable for IIS; <br> 2. Thread safe is suitable for PHP running in module mode, and Non-thread safe is suitable for CGI running mode. <br> Modify php.ini, add: extension=php_mongo.dll, and restart the web server. </p> <p>Ubuntu installation steps: </p> <p>1. Download the plug-in: mongo-php-driver</p> <p>2. Unzip and install: </p> <div class="code" style="position:relative; padding:0px; margin:0px;"><pre class="brush:php;toolbar:false;"> $ tar zxvf mongodb-mongodb-php-driver-<commit_id>.tar.gz $ cd mongodb-mongodb-php-driver-<commit_id> $ phpize $ ./configure $ make all $ sudo make install</commit_id></commit_id></pre><div class="contentsignin">Copy after login</div></div> <p>3. Configure php.ini</p> <p>#extension=uploadprogress.so<br> #extension=http.so<br> #extension=intl.so<br> #extension=curl.so</p> <p>extension=/usr/lib/php5/20121212/curl.so<br> extension=/usr/lib/php5/20121212/gd.so<br> extension=/usr/lib/php5/20121212/json.so<br> extension=/usr/lib/php5/20121212/mysql.so<br> extension=/usr/lib/php5/20121212/mysqli.so<br> #extension=/usr/lib/php5/20121212/opcache.so<br> extension=/usr/lib/php5/20121212/pdo.so<br> extension=/usr/lib/php5/20121212/pdo_mysql.so<br> #extension=/usr/lib/php5/20121212/readline.so<br> #extension=/usr/lib/php5/20121212/xdebug.so<br> extension=/usr/local/lib/php/extensions/no-debug-non-zts-20121212/redis.so<br> extension=/usr/local/lib/php/extensions/no-debug-non-zts-20121212/mongo.so</p> <p>4. Restart apache</p> <p>sudo /etc/init.d/apache2 restart</p> <p>5. Modify the default startup items (optional) </p> <p>sudo vim /etc/apache2/apache2.conf</p> <p>Add the configuration code as follows: </p> <table border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td class="gutter">1234567891011121314</td> <td class="code"><code class="python" plain=""><virtualhost code=""><code class="python" keyword="">*</code><code class="python" plain="">:</code><code class="python" value="">80</code><code class="python" plain="">></code><code class="python" spaces=""> </code><code class="python" plain="">ServerAdmin webmaster@localhost</code><code class="python" spaces=""> </code><code class="python" plain="">DocumentRoot </code><code class="python" keyword="">/</code><code class="python" plain="">home</code><code class="python" keyword="">/</code><code class="python" plain="">homer</code><code class="python" keyword="">/</code><code class="python" plain="">workspace</code><code class="python" spaces=""> </code><code class="python" plain=""><directory code=""><code class="python" keyword="">/</code><code class="python" plain="">home</code><code class="python" keyword="">/</code><code class="python" plain="">homer</code><code class="python" keyword="">/</code><code class="python" plain="">workspace</code><code class="python" keyword="">/</code><code class="python" plain="">money_client></code><code class="python" spaces=""> </code><code class="python" plain="">DirectoryIndex index.html index.php</code><code class="python" spaces=""> </code><code class="python" plain="">Options Indexes FollowSymLinks</code><code class="python" spaces=""> </code><code class="python" plain="">AllowOverride </code><code class="python" color1="">None</code><code class="python" spaces=""> </code><code class="python" plain="">Require </code><code class="python" functions="">all</code> <code class="python" plain="">granted</code><code class="python" spaces=""> </code><code class="python" plain=""><</code><code class="python" keyword="">/</code><code class="python" plain="">Directory></code><code class="python" spaces=""> </code><code class="python" plain="">ServerName localhost</code><code class="python" spaces=""> </code><code class="python" plain="">DirectoryIndex index.html index.php</code><code class="python" spaces=""> </code><code class="python" plain="">ErrorLog ${APACHE_LOG_DIR}</code><code class="python" keyword="">/</code><code class="python" plain="">error_alibuyer.log</code><code class="python" spaces=""> </code><code class="python" plain="">CustomLog ${APACHE_LOG_DIR}</code><code class="python" keyword="">/</code><code class="python" plain="">access_alibuyer.log combined</code><code class="python" plain=""><</code><code class="python" keyword="">/</code><code class="python" plain="">VirtualHost></code></directory></code></virtualhost></code></td> </tr> </tbody> </table> <p> </p> <p><strong>4. PHP example</strong></p> <p><strong>1. Connect to Mongo server </strong></p> <table border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td class="gutter">1234567891011121314</td> <td class="code"><code class="php" plain=""><code class="php" variable="">$conn</code> <code class="php" plain="">= </code><code class="php" keyword="">new</code> <code class="php" plain="">Mongo(); </code><code class="php" comments="">// 连接localhost:27017</code><code class="php" spaces=""> </code><code class="php" variable="">$conn</code> <code class="php" plain="">= </code><code class="php" keyword="">new</code> <code class="php" plain="">Mongo(</code><code class="php" string="">'test.com'</code><code class="php" plain="">); </code><code class="php" comments="">// 连接远程主机默认端口 </code><code class="php" spaces=""> </code><code class="php" variable="">$conn</code> <code class="php" plain="">= </code><code class="php" keyword="">new</code> <code class="php" plain="">Mongo(</code><code class="php" string="">'test.com:22011'</code><code class="php" plain="">); </code><code class="php" comments="">//连接远程主机22011端口</code> <code class="php" spaces=""> </code><code class="php" comments="">// MongoDB有用户名密码</code><code class="php" spaces=""> </code><code class="php" variable="">$conn</code> <code class="php" plain="">= </code><code class="php" keyword="">new</code> <code class="php" plain="">Mongo(</code><code class="php" string="">mongodb://${username}:${password}@localhost</code><code class="php" plain="">); </code> <code class="php" spaces=""> </code><code class="php" comments="">// MongoDB有用户名密码并指定数据库blog </code><code class="php" spaces=""> </code><code class="php" variable="">$conn</code> <code class="php" plain="">= </code><code class="php" keyword="">new</code> <code class="php" plain="">Mongo(</code><code class="php" string="">mongodb://${username}:${password}@localhost/blog</code><code class="php" plain="">);</code><code class="php" spaces=""> </code> <code class="php" spaces=""> </code><code class="php" comments="">// 多个服务器</code><code class="php" spaces=""> </code><code class="php" variable="">$conn</code> <code class="php" plain="">= </code><code class="php" keyword="">new</code> <code class="php" plain="">Mongo(</code><code class="php" string="">mongodb://localhost:27017,localhost:27018</code><code class="php" plain="">); </code><code class="php" plain="">?></code></code></td> </tr> </tbody> </table> <p>Or use <strong> MongoClient()</strong></p> <table border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td class="gutter">1234567891011121314151617</td> <td class="code"><code class="php" plain=""><code class="php" variable="">$MONGO_SERVER</code> <code class="php" plain="">= </code><code class="php" keyword="">array</code><code class="php" plain="">( </code><code class="php" string="">'host'</code><code class="php" plain="">=></code><code class="php" string="">'10.123.55.16'</code><code class="php" plain="">,</code><code class="php" spaces=""> </code><code class="php" string="">'port'</code><code class="php" plain="">=>27017,</code><code class="php" spaces=""> </code><code class="php" string="">'dbname'</code><code class="php" plain="">=></code><code class="php" string="">'mimvp_money'</code><code class="php" plain="">,</code><code class="php" spaces=""> </code><code class="php" string="">'user'</code><code class="php" plain="">=></code><code class="php" string="">''</code><code class="php" plain="">,</code><code class="php" spaces=""> </code><code class="php" string="">'pwd'</code><code class="php" plain="">=></code><code class="php" string="">''</code><code class="php" plain="">);</code> <code class="php" spaces=""> </code><code class="php" variable="">$count</code> <code class="php" plain="">= </code><code class="php" variable="">$coll</code><code class="php" plain="">-></code><code class="php" functions="">count</code><code class="php" plain="">();</code><code class="php" spaces=""> </code><code class="php" functions="">print</code><code class="php" plain="">(</code><code class="php" string="">count: </code> <code class="php" plain="">. </code><code class="php" variable="">$count</code><code class="php" plain="">);</code><code class="php" spaces=""> </code> <code class="php" spaces=""> </code><code class="php" variable="">$host_port</code> <code class="php" plain="">= </code><code class="php" variable="">$MONGO_SERVER</code><code class="php" plain="">[</code><code class="php" string="">'host'</code><code class="php" plain="">] . </code><code class="php" string="">:</code> <code class="php" plain="">. </code><code class="php" variable="">$MONGO_SERVER</code><code class="php" plain="">[</code><code class="php" string="">'port'</code><code class="php" plain="">]; </code><code class="php" comments="">// '10.123.55.16:20517'</code><code class="php" spaces=""> </code> <code class="php" spaces=""> </code><code class="php" variable="">$conn</code> <code class="php" plain="">= </code><code class="php" keyword="">new</code> <code class="php" plain="">MongoClient(</code><code class="php" variable="">$host_port</code><code class="php" plain="">);</code><code class="php" spaces=""> </code><code class="php" variable="">$db</code> <code class="php" plain="">= </code><code class="php" variable="">$conn</code><code class="php" plain="">->selectDB(</code><code class="php" variable="">$MONGO_SERVER</code><code class="php" plain="">[</code><code class="php" string="">'dbname'</code><code class="php" plain="">]);</code><code class="php" spaces=""> </code><code class="php" variable="">$coll</code> <code class="php" plain="">= </code><code class="php" keyword="">new</code> <code class="php" plain="">MongoCollection(</code><code class="php" variable="">$db</code><code class="php" plain="">, </code><code class="php" variable="">$connName</code><code class="php" plain="">);</code><code class="php" spaces=""> </code><code class="php" variable="">$conn</code><code class="php" plain="">->close();</code><code class="php" plain="">?></code></code></td> </tr> </tbody> </table> <p> </p> <p><strong>2. Specify database and data set name </strong> (table name) </p> <table border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td class="gutter">1234</td> <td class="code"><code class="php" plain=""><code class="php" variable="">$db</code> <code class="php" plain="">= </code><code class="php" variable="">$conn</code><code class="php" plain="">->blog; </code><code class="php" comments="">// 选择数据库blog</code><code class="php" spaces=""> </code><code class="php" variable="">$collection</code> <code class="php" plain="">= </code><code class="php" variable="">$db</code><code class="php" plain="">->users; </code><code class="php" comments="">// 制定结果集（表名：users）</code><code class="php" plain="">?> </code></code></td> </tr> </tbody> </table> <p> </p> <p><strong>3. CRUD operation</strong></p> <table border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td class="gutter">123456789101112131415</td> <td class="code"><code class="php" plain=""><code class="php" variable="">$user</code> <code class="php" plain="">= </code><code class="php" keyword="">array</code><code class="php" plain="">(</code><code class="php" string="">'name'</code> <code class="php" plain="">=> </code><code class="php" string="">'caleng'</code><code class="php" plain="">, </code><code class="php" string="">'email'</code> <code class="php" plain="">=> </code><code class="php" string="">'[email protected]'</code><code class="php" plain="">); </code><code class="php" comments="">// 新增 </code><code class="php" spaces=""> </code><code class="php" variable="">$collection</code><code class="php" plain="">->insert(</code><code class="php" variable="">$user</code><code class="php" plain="">); </code><code class="php" spaces=""> </code> <code class="php" spaces=""> </code><code class="php" variable="">$newdata</code> <code class="php" plain="">= </code><code class="php" keyword="">array</code><code class="php" plain="">(</code><code class="php" string="">'$set'</code> <code class="php" plain="">=> </code><code class="php" keyword="">array</code><code class="php" plain="">(</code><code class="php" string="">email</code> <code class="php" plain="">=> </code><code class="php" string="">[email protected]</code><code class="php" plain="">)); </code><code class="php" comments="">// 修改</code><code class="php" spaces=""> </code><code class="php" variable="">$collection</code><code class="php" plain="">->update(</code><code class="php" keyword="">array</code><code class="php" plain="">(</code><code class="php" string="">name</code> <code class="php" plain="">=> </code><code class="php" string="">caleng</code><code class="php" plain="">), </code><code class="php" variable="">$newdata</code><code class="php" plain="">); </code><code class="php" spaces=""> </code> <code class="php" spaces=""> </code><code class="php" variable="">$collection</code><code class="php" plain="">->remove(</code><code class="php" keyword="">array</code><code class="php" plain="">(</code><code class="php" string="">'name'</code><code class="php" plain="">=></code><code class="php" string="">'caleng'</code><code class="php" plain="">), </code><code class="php" keyword="">array</code><code class="php" plain="">(</code><code class="php" string="">justOne</code> <code class="php" plain="">=> true)); </code><code class="php" comments="">// 删除</code><code class="php" spaces=""> </code> <code class="php" spaces=""> </code><code class="php" variable="">$cursor</code> <code class="php" plain="">= </code><code class="php" variable="">$collection</code><code class="php" plain="">->find(); </code><code class="php" comments="">// 查找 </code><code class="php" spaces=""> </code><code class="php" plain="">var_dump(</code><code class="php" variable="">$cursor</code><code class="php" plain="">); </code><code class="php" spaces=""> </code> <code class="php" spaces=""> </code><code class="php" variable="">$user</code> <code class="php" plain="">= </code><code class="php" variable="">$collection</code><code class="php" plain="">->findOne(</code><code class="php" keyword="">array</code><code class="php" plain="">(</code><code class="php" string="">'name'</code> <code class="php" plain="">=> </code><code class="php" string="">'caleng'</code><code class="php" plain="">), </code><code class="php" keyword="">array</code><code class="php" plain="">(</code><code class="php" string="">'email'</code><code class="php" plain="">)); </code><code class="php" comments="">// 查找一条</code><code class="php" spaces=""> </code><code class="php" plain="">var_dump(</code><code class="php" variable="">$user</code><code class="php" plain="">); </code><code class="php" plain="">?></code></code></td> </tr> </tbody> </table> <p> </p> <p><strong>4. Close the connection </strong></p> <table border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td class="gutter">123</td> <td class="code"><code class="php" plain=""><code class="php" variable="">$conn</code><code class="php" plain="">->close(); </code><code class="php" plain="">?></code></code></td> </tr> </tbody> </table> <p> </p> <p><strong>5. Sample code</strong></p> <table border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td class="gutter">123456789101112131415161718192021222324252627282930313233343536373839</td> <td class="code"><code class="php" plain=""><code class="php" comments="">//这里采用默认连接本机的27017端口，当然你也可以连接远程主机如192.168.0.4:27017,如果端口是27017，端口可以省略 </code><code class="php" spaces=""> </code><code class="php" variable="">$m</code> <code class="php" plain="">= </code><code class="php" keyword="">new</code> <code class="php" plain="">Mongo(); </code> <code class="php" spaces=""> </code><code class="php" comments="">// 选择comedy数据库，如果以前没该数据库会自动创建，也可以用$m->selectDB(comedy); </code><code class="php" spaces=""> </code><code class="php" variable="">$db</code> <code class="php" plain="">= </code><code class="php" variable="">$m</code><code class="php" plain="">->comedy; </code> <code class="php" spaces=""> </code><code class="php" comments="">//选择comedy里面的collection集合，相当于RDBMS里面的表，也-可以使用 </code><code class="php" spaces=""> </code><code class="php" variable="">$collection</code> <code class="php" plain="">= </code><code class="php" variable="">$db</code><code class="php" plain="">->collection; </code><code class="php" spaces=""> </code><code class="php" variable="">$db</code><code class="php" plain="">->selectCollection(</code><code class="php" string="">collection</code><code class="php" plain="">);</code><code class="php" spaces=""> </code> <code class="php" spaces=""> </code><code class="php" comments="">//添加一个元素 </code><code class="php" spaces=""> </code><code class="php" variable="">$obj</code> <code class="php" plain="">= </code><code class="php" keyword="">array</code><code class="php" plain="">( </code><code class="php" string="">title</code> <code class="php" plain="">=> </code><code class="php" string="">Calvin and Hobbes-</code><code class="php" plain="">.</code><code class="php" functions="">date</code><code class="php" plain="">(</code><code class="php" string="">'i:s'</code><code class="php" plain="">), </code><code class="php" string="">author</code> <code class="php" plain="">=> </code><code class="php" string="">Bill Watterson</code> <code class="php" plain="">); </code> <code class="php" spaces=""> </code><code class="php" comments="">//将$obj 添加到$collection 集合中 </code><code class="php" spaces=""> </code><code class="php" variable="">$collection</code><code class="php" plain="">->insert(</code><code class="php" variable="">$obj</code><code class="php" plain="">); </code> <code class="php" spaces=""> </code><code class="php" comments="">//添加另一个元素 </code><code class="php" spaces=""> </code><code class="php" variable="">$obj</code> <code class="php" plain="">= </code><code class="php" keyword="">array</code><code class="php" plain="">( </code><code class="php" string="">title</code> <code class="php" plain="">=> </code><code class="php" string="">XKCD-</code><code class="php" plain="">.</code><code class="php" functions="">date</code><code class="php" plain="">(</code><code class="php" string="">'i:s'</code><code class="php" plain="">), </code><code class="php" string="">online</code> <code class="php" plain="">=> true ); </code><code class="php" spaces=""> </code><code class="php" variable="">$collection</code><code class="php" plain="">->insert(</code><code class="php" variable="">$obj</code><code class="php" plain="">); </code> <code class="php" spaces=""> </code><code class="php" comments="">//查询所有的记录 </code><code class="php" spaces=""> </code><code class="php" variable="">$cursor</code> <code class="php" plain="">= </code><code class="php" variable="">$collection</code><code class="php" plain="">->find(); </code> <code class="php" spaces=""> </code><code class="php" comments="">//遍历所有集合中的文档 </code><code class="php" spaces=""> </code><code class="php" keyword="">foreach</code> <code class="php" plain="">(</code><code class="php" variable="">$cursor</code> <code class="php" keyword="">as</code> <code class="php" variable="">$obj</code><code class="php" plain="">) </code><code class="php" spaces=""> </code><code class="php" plain="">{ </code><code class="php" spaces=""> </code><code class="php" functions="">echo</code> <code class="php" variable="">$obj</code><code class="php" plain="">[</code><code class="php" string="">title</code><code class="php" plain="">] . </code><br><code class="php" plain="">; </code><code class="php" spaces=""> </code><code class="php" plain="">} </code> <code class="php" spaces=""> </code><code class="php" comments="">//删除所有数据 </code><code class="php" spaces=""> </code><code class="php" comments="">//$collection->remove(); </code> <code class="php" spaces=""> </code><code class="php" comments="">//删除 name 为hm </code><code class="php" spaces=""> </code><code class="php" comments="">//$collection->remove(array('name'=>'hm')); </code> <code class="php" spaces=""> </code><code class="php" comments="">//断开MongoDB连接 </code><code class="php" spaces=""> </code><code class="php" variable="">$m</code><code class="php" plain="">->close(); </code><code class="php" plain="">?></code></code></td> </tr> </tbody> </table> <p> </p> <p><b> </b></p> <p align="left"></p> <div style="display:none;"> <span id="url" itemprop="url">http://www.bkjia.com/PHPjc/1065656.html</span><span id="indexUrl" itemprop="indexUrl">www.bkjia.com</span><span id="isOriginal" itemprop="isOriginal">true</span><span id="isBasedOnUrl" itemprop="isBasedOnUrl">http: //www.bkjia.com/PHPjc/1065656.html</span><span id="genre" itemprop="genre">TechArticle</span><span id="description" itemprop="description">PHP operating MongoDB database 1. Introduction to MongoDB MongoDB (the name comes from humongous) is a scalable, high-performance, open source , model-free, document-oriented database, integrated document database...</span> </div> <div class="art_confoot"></div>

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iOS 18 adds a new 'Recovered' album function to retrieve lost or damaged photos Jul 18, 2024 am 05:48 AM

Apple's latest releases of iOS18, iPadOS18 and macOS Sequoia systems have added an important feature to the Photos application, designed to help users easily recover photos and videos lost or damaged due to various reasons. The new feature introduces an album called "Recovered" in the Tools section of the Photos app that will automatically appear when a user has pictures or videos on their device that are not part of their photo library. The emergence of the "Recovered" album provides a solution for photos and videos lost due to database corruption, the camera application not saving to the photo library correctly, or a third-party application managing the photo library. Users only need a few simple steps

Detailed tutorial on establishing a database connection using MySQLi in PHP Jun 04, 2024 pm 01:42 PM

How to use MySQLi to establish a database connection in PHP: Include MySQLi extension (require_once) Create connection function (functionconnect_to_db) Call connection function ($conn=connect_to_db()) Execute query ($result=$conn->query()) Close connection ( $conn->close())

An in-depth analysis of how HTML reads the database Apr 09, 2024 pm 12:36 PM

HTML cannot read the database directly, but it can be achieved through JavaScript and AJAX. The steps include establishing a database connection, sending a query, processing the response, and updating the page. This article provides a practical example of using JavaScript, AJAX and PHP to read data from a MySQL database, showing how to dynamically display query results in an HTML page. This example uses XMLHttpRequest to establish a database connection, send a query and process the response, thereby filling data into page elements and realizing the function of HTML reading the database.

How to handle database connection errors in PHP Jun 05, 2024 pm 02:16 PM

To handle database connection errors in PHP, you can use the following steps: Use mysqli_connect_errno() to obtain the error code. Use mysqli_connect_error() to get the error message. By capturing and logging these error messages, database connection issues can be easily identified and resolved, ensuring the smooth running of your application.

Analysis of the basic principles of MySQL database management system Mar 25, 2024 pm 12:42 PM

Analysis of the basic principles of the MySQL database management system MySQL is a commonly used relational database management system that uses structured query language (SQL) for data storage and management. This article will introduce the basic principles of the MySQL database management system, including database creation, data table design, data addition, deletion, modification, and other operations, and provide specific code examples. 1. Database Creation In MySQL, you first need to create a database instance to store data. The following code can create a file named "my

Tips and practices for handling Chinese garbled characters in databases with PHP Mar 27, 2024 pm 05:21 PM

PHP is a back-end programming language widely used in website development. It has powerful database operation functions and is often used to interact with databases such as MySQL. However, due to the complexity of Chinese character encoding, problems often arise when dealing with Chinese garbled characters in the database. This article will introduce the skills and practices of PHP in handling Chinese garbled characters in databases, including common causes of garbled characters, solutions and specific code examples. Common reasons for garbled characters are incorrect database character set settings: the correct character set needs to be selected when creating the database, such as utf8 or u

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