Web Developer Zone
Web Developer Zone is a code first section devoted to tools and techniques used in web development. Thematically, the main focus here is on PHP, Linux, BASH, JavaScript and a little bit of MySQL and Python.
Pick of the week
![Using arrow functions for recursive post-order tree traversal](https://swww.com.pl/media/img/post/80_head-320x126.jpg)
Using arrow functions for recursive post-order tree traversal
24 Jul 2020 00:31:31
Using JavaScript arrow functions for post-order based tree data structure traversal.
Popular
![Piping JSON object to PHP script](https://swww.com.pl/media/img/post/84_head-320x126.jpg)
03 Aug 2020 00:39:31
Piping JSON object to PHP script
Article about how to pass data from a shell to a PHP script with a pipe on the command line or directly using PHP system function.
![Fixing No input file specified error in CodeIgniter 4](https://swww.com.pl/media/img/post/108_head-320x126.jpg)
29 Jul 2023 17:05:58
Fixing No input file specified error in CodeIgniter 4
Get rid of No input file specified error in CodeIgniter 4.
![Transforming range of variable to 0 to 1 and custom ranges](https://swww.com.pl/media/img/post/79_head-320x126.jpg)
18 Jul 2020 00:39:07
Transforming range of variable to 0 to 1 and custom ranges
Learn how to transform variable's range to [0,1] or a custom range.
![Mapping associative array keys to variables with $$ in PHP](https://swww.com.pl/media/img/post/87_head-320x126.jpg)
20 May 2021 17:49:23
Mapping associative array keys to variables with $$ in PHP
A neat trick to reduce amount of code needed to access data stored in PHP associative array.
![MongoDB mongod server fails to start after installation and solution](https://swww.com.pl/media/img/post/102_head-320x126.jpg)
07 Apr 2022 00:55:48
MongoDB mongod server fails to start after installation and solution
MongoDB server not starting after installation due to missing dependencies and how to solve this problem.
![There is no data to update error in CodeIgniter 4](https://swww.com.pl/media/img/post/109_head-320x126.jpg)
24 May 2024 11:51:01
There is no data to update error in CodeIgniter 4
Finding a solution to There is no data to update error in CodeIgniter 4.
Recent
![Performing inner and outer SQL joins in CodeIgniter 4](https://swww.com.pl/media/img/post/101_head-320x126.jpg)
04 Feb 2022 22:19:19
Performing inner and outer SQL joins in CodeIgniter 4
In this post I look at how to perform inner and outer SQL joins using CodeIgniter 4 prepared queries and Query Builder class. I assume you know what SQL joins are and when to use them in MySQL. This article describes a specific situation. There are three tables, posts, galleries ...
![Prepending an empty string key option to options array for form_dropdown function in CodeIgniter 4](https://swww.com.pl/media/img/post/100_head-320x126.jpg)
04 Feb 2022 00:47:56
Prepending an empty string key option to options array for form_dropdown function in CodeIgniter 4
A couple of sentences on how to prepend an options array, which contains numerical keys with a non-numerical key option for form_dropdown function in CodeIgniter 4. The option could be something like, '' => 'Choose ...' . One very good, probably the best, ...
![Adding, listing and dropping foreign keys in MySQL](https://swww.com.pl/media/img/post/99_head-320x126.jpg)
02 Feb 2022 00:17:15
Adding, listing and dropping foreign keys in MySQL
This time a couple of words on how to add, list and drop foreign keys with ON CASCADE DELETE clause. What are foreign keys for? You define your foreign keys on tables to ensure integrity of your data. One particular case of this is a foreign key with ON CASCADE DELETE clause. ...
![Finding previous and next database table item with Query Builder in CodeIgniter 4](https://swww.com.pl/media/img/post/98_head-320x126.jpg)
28 Jan 2022 21:39:38
Finding previous and next database table item with Query Builder in CodeIgniter 4
Imagine you have a database table Posts with items like blog posts, news and pages. Each of those items has its unique id and type like "page" or "news". Given an id of a database item, your goal is to find the previous and the next item of the same type ...
SWWW
![S.Wojnowski - web developer](https://swww.com.pl/media/img/swww_intro_1.png)
SWWW is my place on the web where I write on stuff related to web development. Main focus here is on my own programs and scripts, but also websites I have developed over years or helped develop, improve or maintain. In the Web Developer Zone I take a closer look at various solutions related to web development and computer programming.
If you find any of my projects interesting, useful or would like to know more on it, do let me know. This website has a contact form. Altenatively, you can leave a comment under an article on the blog.
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