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OpenLamp.tech issue #8

It’s that time once again. I’ve published another issue of OpenLamp.tech, the newsletter for PHP/MySQL developers, over the weekend with all the curated content for your reading experience. There is plenty to learn for everyone so dig in…

I start my day every day with Refind. You should too.

Self-Promotion:

If you enjoy the content written here, by all means, share this blog and your favorite post(s) with others who may benefit from or like it as well. Since coffee is my favorite drink, you can even buy me one if you would like!

This week in the OpenLamp.tech newsletter, we have articles covering:

  • WordPress theme migration checklist
  • Form validation in CodeIgniter 4
  • …
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My Friendly Medium List

Hey everyone, I’m creating a dedicated page of ‘Friend links‘ for all of my Medium first articles and blogs. Continue reading to learn more and how to gain access to them…

Image by David Schwarzenberg from Pixabay

Medium’s Friend Link

If you’re a paying Medium member, not only can you read unlimited blog posts by any author on the platform, but you can also publish your blog posts and articles behind the paywall and earn some money from them. Every article you put behind the paywall also has a ‘Friend …

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OpenLamp.tech #7 – MySQL Metadata with CodeIgniter 4

After taking the week of Christmas off, OpenLamp.tech – the newsletter for PHP/MySQL developers – is back with a massive issue for you this week to close out the month and the year. In this issue, we are covering MySQL metadata in CodeIgniter 4. Continue reading for more information…

Self-Promotion:

If you enjoy the content written here, by all means, share this blog and your favorite post(s) with others who may benefit from or like it as well. Since coffee is my favorite drink, you can even buy me one if you would like!

This deep-dive featured issue is full of PHP/MySQL goodness. We are looking …

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5 PHP Date Functions and Their MySQL Equivalents

Anyone working with data is going to encounter date values at some point. Dates are necessary for many reasons. If you’re a PHP/MySQL Developer, you have date function options for both the database and your programming language of choice. In this post, I cover 5 PHP date functions and their (somewhat) MySQL equivalents with examples of each. Continue reading…

Self-Promotion:

If you enjoy the content written here, by all means, share this blog and your favorite post(s) with others who may benefit from or like it as well. Since coffee is my favorite drink, you can even buy me one if you would like!

The Newsletter for PHP and MySQL Developers

Table Of Contents

  1. PHP: date_format() | MySQL: DATE_FORMAT()
  2. …
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CodeIgniter 4 Query Builder set() function with update()

CodeIgniter 4 Query Builder class has an update() function used to process UPDATE Data Manipulation Language (DML) commands. Using update() as a standalone function call is perfectly valid. However, there is also a set() function used for setting column values as you would with the SET keyword in an SQL UPDATE statement. Used in conjunction with the Query Builder where() function, you can easily UPDATE column values for an individual row or multiple rows. Continue reading for more information…

Image by  …

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OpenLamp.tech issue #6

Hey all good folks! I’ve published another issue of your favorite newsletter, OpenLamp.tech, the newsletter for PHP/MySQL developers. This issue (like all the rest) is loaded with fantastic curated content. Enjoy and do share with others!

Self-Promotion:

If you enjoy the content written here, by all means, share this blog and your favorite post(s) with others who may benefit from or like it as well. Since coffee is my favorite drink, you can even buy me one if you would like!

I enjoy writing and curating the OpenLamp.tech newsletter. If you would like to support my efforts and you are finding value in the weekly publication, please share this post or an issue with someone you think would value the content as well.

The Newsletter for PHP and MySQL Developers

In this week’s issue, we have …

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Rails that scales - Powered by Vitess

Past - Frameworks without scale # Over the past couple of decades, there has been a steady rise in the complexity of the development stacks that the developers across the globe have been using. The web has advanced from being just HTML files, to also include CSS and JavaScript with their own multitudes of frameworks like Redwood, Next.js, and Angular, among many others. The number of library dependencies that each project has has also shot up, leading to package managers like npm gaining popularity.

Read CSV with Python

In 2009, I showed an example of how to use the MySQL LOAD DATA INFILE command. Last year, I updated the details to reset the secure_file-priv privilege to use the LOAD DATA INFILE command, but you can avoid that approach with a simple Python 3 program like the one in this example. You also can use MySQL Shell’s new parallel table import feature, introduced in 8.0.17, as noted in a comment on this blog post.

The example requires creating an avenger table, avenger.csv file, a readWriteData.py Python script, run the readWriteData.py Python script, and a query that validates the insertion of the avenger.csv file’s data into the avenger table. The complete code in five steps using the sakila demonstration database:

  • Creating the …
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MySQL Query Performance

Working through our chapter on MySQL views, I wrote the query two ways to introduce the idea of SQL tuning. That’s one of the final topics before introducing JSON types.

I gave the students this query based on the Sakila sample database after explaining how to use the EXPLAIN syntax. The query only uses only inner joins, which are generally faster and more efficient than subqueries as a rule of thumb than correlated subqueries.

SELECT   ctry.country AS country_name
,        SUM(p.amount) AS tot_payments
FROM     city c INNER JOIN address a
ON       c.city_id = a.city_id INNER JOIN customer cus
ON       a.address_id = cus.address_id INNER JOIN payment p
ON       cus.customer_id = p.customer_id INNER JOIN country ctry
ON       c.country_id = ctry.country_id
GROUP BY ctry.country;

It generated the following tabular explain plan output:

 …
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MySQL DropIndexIfExists

In reply to a question about how to conditionally drop an index on a table in MySQL. It appears the syntax doesn’t exist. However, maybe it does and I missed it. If I did miss it, I’m sure somebody will let me know. However, I simply have a dropIndexIfExists stored procedure for this type of database maintenance.

Below is my dropIndexIfExists stored procedure:

-- Conditionally drop the procedure.
DROP PROCEDURE IF EXISTS dropIndexIfExists;

-- Change the default semicolon delimiter to write a PSM
-- (Persistent Stored Module) or stored procedure.
DELIMITER $$

-- Create the procedure.
CREATE PROCEDURE dropIndexIfExists
( pv_table_name  VARCHAR(64)
, pv_index_name  VARCHAR(64))
BEGIN

  /* Declare a local variable for the SQL statement. */
  DECLARE stmt VARCHAR(1024);

  /* Set a session variable with two parameter markers. */
  SET @SQL := CONCAT('ALTER TABLE ',pv_table_name,'DROP INDEX ',pv_index_name);

  /* Check if the constraint exists. …
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