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…

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The Newsletter for PHP and MySQL Developers

In this week’s issue, we have …

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.

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 …

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:

 …

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. …

I was working through some tutorials for my students and noticed that there was a change in how a WHERE clause must be written against the information_schema.table_constraints table. It might have been made in an earlier release, I actually hadn’t checked it since 2014 when I wrote this early post on capturing MySQL Foreign Keys.

You could use the following WHERE case insensitive clause:

WHERE    tc.constraint_type = 'foreign key'

Now, you must use a case sensitive WHERE clause:

WHERE    tc.constraint_type = 'FOREIGN KEY'

I’d love to know why but I can’t seem to find a note on the change. As always, I hope this helps those looking for an answer.

I recently learned how to use MySQL to generate MySQL statements for several admin-type Data Definition Language (DDL) SQL queries I needed to execute on the server. For many DBA’s this is likely nothing new and in fact, is a well-used tool in their kit. However, I mostly focus on developer-related tasks, so it is a fresh-in-my-mind learning experience. Continue reading for more information…

Some backstory for context

I’ve recently been porting over an existing vanilla PHP application to CodeIgniter 4. One of the new features is bootstrapping all of the necessary MySQL CREATE TABLE statements dynamically based on information parsed from a .fxl file (which is close kin to a .xml file structure-wise).

Each CREATE TABLE statement is complete with FOREIGN KEY constraint clauses to ensure data integrity between linking …

Hey friends over the weekend (Friday actually) I’ve published another issue of my weekly newsletter, OpenLamp.tech. Continue reading for more information…

This issue is full of great curated reads as well as a specific question I’ve asked readers and the community. Looking for some suggestions on planned migrations for upgrades to my WordPress site.

The Newsletter for PHP and MySQL Developers

In this weeks newsletter, there’s information on:

Here’s the full issue for you to read. You can always subscribe (it’s free) and have the weekly issue of OpenLamp.tech delivered directly to your inbox. Just think, no more waiting for me to post it here each Monday.

Visit the sign-up form below to …

Generally, most all web applications are going to follow the elements of CRUD: Create, Read, Update, and Delete. CodeIgniter 4 is a powerful PHP web development framework that provides a rapid development environment. The CodeIgniter 4 Models come enriched with built-in CRUD functionality, which is covered in this compilation of Medium posts…

Image by Dariusz Sankowski from Pixabay 

Disclaimer: I originally published these articles first over on …