Be it running reports or displaying data in some other visualization, SQL SELECT column expressions should be meaningful and understandable. To provide those valuable query results, SQL Developers, use a multitude of available functions, adjacent columns, or other means not readily apparent to end-users. All that being said, the column names often suffer the most as far as readability is concerned, taking on long function call names or other combined expressions. But, as luck would be on our side, there is an easy fix and that is aliasing columns using the AS keyword. Although AS is optional – in this particular context – I err on the side of readability and use it when aliasing SELECT column expressions.

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Introduction In this article, we are going to see what a Clustered Index is and why it’s very important to understand how tables are organized when using a relational database system. B+ Tree The most common index used in a relational database system is the B+ Tree one. Like the B-Tree index, the B+ Tree is a self-balanced ordered tree data structure. Both the B-Tree and the B-Tree start from a Root node and may have Internal Nodes and Leaf Nodes. However, unlike the B-Tree, the B+ Tree stores all the keys... Read More

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Any of you who read my blog posts here regularly know I am passionate about SQL, PHP, and Back-end Development. I consider writing an integral part of my brand and growth. Continue reading and learn more about what’s on my mind lately with writing and code…

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Each SQL dialect is different in some way, shape, form, or fashion from the next flavor. Some dialects have this function, while others have that function. In this post, I cover porting over Oracle SQL to MySQL in order to count the number of occurrences of a specific weekday found in the current given month (at the time of writing) purely as a learning exercise focused on MySQL DATE functions and the WITH clause…

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Sometimes clients want that the information they collected from the user should be encrypted and stored in a database. Data encryption and…

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I recently published a blog post over on Medium about the differences in 2 versions of the MySQL COUNT() aggregate function: COUNT(*) and COUNT(column_name or expression). I wanted to share the post here with any readers who may be interested so continue reading for more on this post…

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In the last post I covered some of the many reasons to migrate data from a spreadsheet to a database and now it is time to show how to do just that.  Moving data from a spreadsheet into MySQL can actually be pretty simple in many cases. Now I will not mislead you by telling you that all cases are easy but there is an easy way to make this migration.  And I highly recommend the following process when possible as it can save lots of time. More painful migrations will be covered in the future but this post is my favorite 'fast and easy' process.

This is a guide to taking data from a spreadsheet and easily moving that data into a MySQL database instance. The trick is the Import Wizard in MySQL Workbench that does a lot of the detail work for you. In a future post we will go into what you have to do when you are not …

CodeIgniter’s Query Builder ORM has class methods for nearly any kind of database access/operation you can think of. In this post, I’ll cover some of the available methods for retrieving aggregate-level query results. The examples in this post map out Query Builder method chaining to produce results you would get from a raw MySQL query. Continue reading to see more…

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Introduction In this article, I’m going to explain how to do query profiling using the MySQL Performance Schema. The Performance Schema has been available since MySQL 5.5.3 and allows MySQL to instrument SQL queries and store their trace information in various tables that you can later inspect in order to determine why a given SQL statement is slow. On older versions of MySQL, you might have used the SHOW PROFILE command, but since this feature has been deprecated, you should now use the Performance Schema for SQL query profiling. Enabling the MySQL... Read More

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Most developers use some form of auto-incrementing integer counter for a given database table, ensuring uniqueness among the rows. Several of the popular SQL dialects implement this facility. For instance, MySQL’s AUTO_INCREMENT attribute is used to provide a unique identity for a table row. What exactly is the behavior of AUTO_INCREMENT? Can you explicitly use a value of your choosing for it if you need to? How does it count? Continue reading and know the answers to these questions and more…

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