数据显示处理
- XML code
<!--Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/-->时间段 机种 数量 2012-02-08 08 ETC56-542N 432012-02-08 09 ETC56-542N 372012-02-08 10 ETC54-623N 162012-02-08 10 ETC54-628N 22
如何处理能变成以下格式?
- XML code
<!--Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/-->时间段 ETC56-542N ETC54-623N ETC54-628N 数量合计 08:00:00-09:00:00 43 4309:00:00-10:00:00 37 3710:00:00-11:00:00 16 22 38
sql查询语句:
- SQL code
<!--Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/-->SELECT DATE_FORMAT(`date`,'%Y-%m-%d %H') as time,type,count(*) as count FROM `barcode_2d` WHERE date >= '".$thisday2." 08:00:00' AND date
------解决方案--------------------
是的,这种情况是交叉表。你可以搜索“交叉表”得到交叉表的定义和算法
当与数据库结合时,有现成的存储过程可以利用。不过算法的技巧性较高,您未必能看得懂
只用 php 实现时,思路很简单:
1、将查询结果保存于数组
2、加工数据到需要的格式
3、对数组做行列转换
4、遍历数组,输出

What’s still popular is the ease of use, flexibility and a strong ecosystem. 1) Ease of use and simple syntax make it the first choice for beginners. 2) Closely integrated with web development, excellent interaction with HTTP requests and database. 3) The huge ecosystem provides a wealth of tools and libraries. 4) Active community and open source nature adapts them to new needs and technology trends.

PHP and Python are both high-level programming languages that are widely used in web development, data processing and automation tasks. 1.PHP is often used to build dynamic websites and content management systems, while Python is often used to build web frameworks and data science. 2.PHP uses echo to output content, Python uses print. 3. Both support object-oriented programming, but the syntax and keywords are different. 4. PHP supports weak type conversion, while Python is more stringent. 5. PHP performance optimization includes using OPcache and asynchronous programming, while Python uses cProfile and asynchronous programming.

PHP is mainly procedural programming, but also supports object-oriented programming (OOP); Python supports a variety of paradigms, including OOP, functional and procedural programming. PHP is suitable for web development, and Python is suitable for a variety of applications such as data analysis and machine learning.

PHP originated in 1994 and was developed by RasmusLerdorf. It was originally used to track website visitors and gradually evolved into a server-side scripting language and was widely used in web development. Python was developed by Guidovan Rossum in the late 1980s and was first released in 1991. It emphasizes code readability and simplicity, and is suitable for scientific computing, data analysis and other fields.

PHP is suitable for web development and rapid prototyping, and Python is suitable for data science and machine learning. 1.PHP is used for dynamic web development, with simple syntax and suitable for rapid development. 2. Python has concise syntax, is suitable for multiple fields, and has a strong library ecosystem.

PHP remains important in the modernization process because it supports a large number of websites and applications and adapts to development needs through frameworks. 1.PHP7 improves performance and introduces new features. 2. Modern frameworks such as Laravel, Symfony and CodeIgniter simplify development and improve code quality. 3. Performance optimization and best practices further improve application efficiency.

PHPhassignificantlyimpactedwebdevelopmentandextendsbeyondit.1)ItpowersmajorplatformslikeWordPressandexcelsindatabaseinteractions.2)PHP'sadaptabilityallowsittoscaleforlargeapplicationsusingframeworkslikeLaravel.3)Beyondweb,PHPisusedincommand-linescrip

PHP type prompts to improve code quality and readability. 1) Scalar type tips: Since PHP7.0, basic data types are allowed to be specified in function parameters, such as int, float, etc. 2) Return type prompt: Ensure the consistency of the function return value type. 3) Union type prompt: Since PHP8.0, multiple types are allowed to be specified in function parameters or return values. 4) Nullable type prompt: Allows to include null values and handle functions that may return null values.


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