


Detailed explanation of the database access function of DreamWeaver CMS
Dream CMS (DEDECMS) is a very popular content management system, of which the database access function is a very important part of it. Through database access, developers can interact with the database and add, delete, modify, and query data. In this article, we will introduce the database access function in DreamWeaver CMS in detail and provide specific code examples.
1. Database connection
In Dreamweaver CMS, database connection is the first step. By connecting to the database, subsequent database operations can be performed. The following is a simple database connection example:
<?php require_once(dirname(__FILE__)."/include/common.inc.php"); $mysql_servername = $GLOBALS['cfg_dbhost']; // 数据库主机地址 $mysql_username = $GLOBALS['cfg_dbuser']; // 数据库用户名 $mysql_password = $GLOBALS['cfg_dbpwd']; // 数据库密码 $mysql_dbname = $GLOBALS['cfg_dbname']; // 数据库名称 $link = mysql_connect($mysql_servername, $mysql_username, $mysql_password); mysql_select_db($mysql_dbname, $link); mysql_query("SET NAMES utf8"); ?>
2. Query data
In Dreamweaver CMS, querying data is a common operation. By executing SQL statements, the required data can be obtained from the database. The following is a simple example of querying data:
<?php $sql = "SELECT * FROM `dede_archives` WHERE `typeid` = 1"; $result = mysql_query($sql); while($row = mysql_fetch_assoc($result)) { echo $row['title'].'<br>'; } ?>
3. Inserting data
Inserting data is one of the commonly used functions in management systems. Data can be inserted into a database table by executing an INSERT statement. The following is a simple example of inserting data:
<?php $title = '测试标题'; $content = '测试内容'; $sql = "INSERT INTO `dede_archives` (`typeid`, `title`, `body`) VALUES (1, '$title', '$content')"; mysql_query($sql); ?>
4. Update data
Updating data is one of the common operations in DreamWeaver CMS. Data in the database can be updated by executing the UPDATE statement. The following is a simple example of updating data:
<?php $title = '更新后的标题'; $content = '更新后的内容'; $sql = "UPDATE `dede_archives` SET `title` = '$title', `body` = '$content' WHERE `aid` = 1"; mysql_query($sql); ?>
5. Delete data
Deleting data is one of the operations that is often required in the management system. Data in a database table can be deleted by executing the DELETE statement. The following is a simple example of deleting data:
<?php $sql = "DELETE FROM `dede_archives` WHERE `aid` = 1"; mysql_query($sql); ?>
Through the above simple code example, the functions of database access in Dreamweaver CMS are demonstrated, including database connection, query data, insert data, update data and delete data, etc. operate. Developers can flexibly use these functions according to actual needs to realize their own project needs. Hope this article is helpful to you.
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