php从数据库中选取ID在数组中存在的记录,并按数组中的顺序排列?该如何处理
php从数据库中选取ID在数组中存在的记录,并按数组中的顺序排列?
比如$arr={"5","7",1"","10","3","8"},要从数据库中选取ID值为5,7,1,10,3,8的记录,并且按这个顺序排列。
------解决方案--------------------
- SQL code
SELECT * FROM table WHERE id IN(5,7,1,10,3,8) ORDER BY FIND_IN_SET(id,'5,7,1,10,3,8'); <br><font color="#e78608">------解决方案--------------------</font><br> //我的测试结果显示PHP排序速度优于MySQL排序速度,刷新了NN次只有1次是PHP慢过MySQL的,请大家也测试一下吧<br><br><?php <br>//date_default_timezone_set('Asia/Shanghai');? <br>$link = mysql_connect('localhost','root');<br>mysql_select_db('test');<br><br>$timeS1 = microtime();<br>$sql = "SELECT * FROM `lean` WHERE id IN(5,7,1,10,3,8) ORDER BY FIND_IN_SET(id,'5,7,1,10,3,8')";<br>//for($i = 1, $i $result = mysql_query($sql);<br> while($row = mysql_fetch_array($result))<br> {<br> <br> }<br>//}<br>$timeE1 = microtime();<br>echo '由数据库自行处理的起止时差为: '.($timeE1 - $timeS1).'<br>';<br><br>//释放译一下php的内存先,免得因为前面的变量影响了效率<br>unset($timeS1);<br>unset($timeS2);<br>unset($link); //已经自动设定了活动数据库了,当前调试不用传递这个,所以把它也释放了吧<br>unset($sql);<br>unset($result);<br>unset($row);<br><br><br><br>//////////////////////<br>$timeS2 = microtime();<br>$sql = "SELECT * FROM `lean` WHERE id IN(5,7,1,10,3,8)";<br>$result = mysql_query($sql);<br>$data = array();<br>$i = 0;<br>while($row = mysql_fetch_array($result))<br>{<br> $data[$row['id']] = $row;<br> $i++;<br>}<br><br>$r = sortdata($data, array(5,7,1,10,3,8));<br><br>$timeE2 = microtime();<br>echo '由PHP处理的起止时差为: '.($timeE2 - $timeS2);<br><br>echo '<pre class="brush:php;toolbar:false">排序结果<br>';<br>print_r($r);<br>echo '
//排序函数
function sortdata($arr,$order){
$r = array();
$i = 0;
foreach($arr as $key => $value){
$r[$order[$i]] = $value;
$i++;
}
return $r;
}

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

AI Hentai Generator
Generate AI Hentai for free.

Hot Article

Hot Tools

Notepad++7.3.1
Easy-to-use and free code editor

SublimeText3 Chinese version
Chinese version, very easy to use

Zend Studio 13.0.1
Powerful PHP integrated development environment

Dreamweaver CS6
Visual web development tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

Hot Topics

Big data structure processing skills: Chunking: Break down the data set and process it in chunks to reduce memory consumption. Generator: Generate data items one by one without loading the entire data set, suitable for unlimited data sets. Streaming: Read files or query results line by line, suitable for large files or remote data. External storage: For very large data sets, store the data in a database or NoSQL.

MySQL query performance can be optimized by building indexes that reduce lookup time from linear complexity to logarithmic complexity. Use PreparedStatements to prevent SQL injection and improve query performance. Limit query results and reduce the amount of data processed by the server. Optimize join queries, including using appropriate join types, creating indexes, and considering using subqueries. Analyze queries to identify bottlenecks; use caching to reduce database load; optimize PHP code to minimize overhead.

Backing up and restoring a MySQL database in PHP can be achieved by following these steps: Back up the database: Use the mysqldump command to dump the database into a SQL file. Restore database: Use the mysql command to restore the database from SQL files.

How to insert data into MySQL table? Connect to the database: Use mysqli to establish a connection to the database. Prepare the SQL query: Write an INSERT statement to specify the columns and values to be inserted. Execute query: Use the query() method to execute the insertion query. If successful, a confirmation message will be output.

One of the major changes introduced in MySQL 8.4 (the latest LTS release as of 2024) is that the "MySQL Native Password" plugin is no longer enabled by default. Further, MySQL 9.0 removes this plugin completely. This change affects PHP and other app

To use MySQL stored procedures in PHP: Use PDO or the MySQLi extension to connect to a MySQL database. Prepare the statement to call the stored procedure. Execute the stored procedure. Process the result set (if the stored procedure returns results). Close the database connection.

Creating a MySQL table using PHP requires the following steps: Connect to the database. Create the database if it does not exist. Select a database. Create table. Execute the query. Close the connection.

Oracle database and MySQL are both databases based on the relational model, but Oracle is superior in terms of compatibility, scalability, data types and security; while MySQL focuses on speed and flexibility and is more suitable for small to medium-sized data sets. . ① Oracle provides a wide range of data types, ② provides advanced security features, ③ is suitable for enterprise-level applications; ① MySQL supports NoSQL data types, ② has fewer security measures, and ③ is suitable for small to medium-sized applications.
