Showing entries 1 to 10 of 22
10 Older Entries »
Displaying posts with tag: Database Developer (reset)
MySQL BETWEEN Operator Queries – Are they inclusive?

I recently learned of some odd behavior using MySQL BETWEEN operator queries, filtering by a DATETIME column. I wrote about this over on Medium so I am sharing the post for any readers here who are interested…

Image by _Alicja_ from Pixabay 

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 …

[Read more]
MySQL Searched CASE Expression – with examples

During many decision-making phases in programming code (conditional logic), there are times execution depends on several different factors. Multiple conditional tests are powerful and constraining, oftentimes requiring more than one test to be passed in order for program flow to proceed. For MySQL (and standard SQL in general) the CASE expression is used for IF/THEN/ELSE conditional logic. The post, MySQL Simple CASE Expression – with examples, covered Simple CASE queries which are essentially equality tests. MySQL Simple CASE is but one variant of 2, with the other being a MySQL Searched CASE Expression.  A MySQL Searched CASE Expression can have multiple conditional tests in each WHEN

[Read more]
MySQL Simple CASE Expression – with examples

Programming logic is foundational in any application or piece of software. Without it, software wouldn’t really do much of anything. Everything happens off of choice. In the end, some truthy or falsy value is what makes stuff work. For IF/THEN/ELSE logic in standard SQL, there is the CASE expression. There are 2 variations of the CASE Expression: Simple and Searched. In this post, I cover the Simple MySQL CASE expression with example queries…

Image by Nika Akin from …

[Read more]
MySQL Column Aliases using the AS keyword

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.

Image by …

[Read more]
MySQL Count Weekday occurrences

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…

Image by tigerlily713 from Pixabay

[Read more]
MySQL COUNT() aggregate function – Medium cross post

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…

Image by anncapictures from Pixabay

Self-Promotion:

If you enjoy the content written here, by …

[Read more]
MySQL’s AUTO_INCREMENT attribute

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…

Image by Gerd Altmann from …

[Read more]
Import CSV file with MySQL Workbench

CSV imports with MySQL Workbench, is super simple. Since CSV’s are probably the most common data interchange format, it goes without saying that importing CSV data into MySQL is a staple task for all DBA’s and Developers. Continue reading to learn how easy it is using MySQL Workbench…

Image by OpenClipart-Vectors from Pixabay

Self-Promotion:

If you enjoy the content written here, by all means, …

[Read more]
MySQL Window Function Compilation

If you use SQL on a regular basis, then you are well aware that Window Functions are powerful. They allow us to simplify queries that would otherwise be quite the mess. We can provide meaningful insight across rows of data without collapsing the results into a single value. I have written numerous blog posts on Window Functions, many here recently. I decided to make this blog post a compilation of all the Window Function posts I have written, providing a one-stop source for any readers interested in learning more about Window Functions…

Image by Free-Photos from …

[Read more]
Top n Window Function queries in MySQL

Top n Window Function queries over a specific subset of data are common in analysis and reporting requirements. Luckily, in MySQL, there are Window functions we can use for this type of query. To be quite honest, you don’t necessarily need Window Functions. You can retrieve those top 3 (or whatever) types of results with a regular SQL query. But, since we have those powerful Window Functions, why not use them? My thoughts exactly! Besides, no one wants a spaghetti code mess of SQL to try and understand. Not to mention, Window functions are often better optimized for querying larger data sets. Continue reading and see example queries for more understanding…

Image by …

[Read more]
Showing entries 1 to 10 of 22
10 Older Entries »