In recent months, there had been some really exciting news from the MySQL team: (Recursive) Common Table Expressions in MySQL Introducing Window Functions These two SQL standard language features are among the most powerful SQL features that are available from most other databases. I frequently include them in conference talks about SQL (see my article … Continue reading jOOQ 3.10 Supports Exciting MySQL 8.0 Features →

The SQL language and its depths... Some of you readers might be aware of MySQL's capability of counting distinct records through the COUNT() aggregate function. The MySQL documentation reads: COUNT(DISTINCT expr,[expr...]) Returns a count of the number of rows with different non-NULL expr values. In other words, you can count distinct first and last names very easily: SELECT … Continue reading Counting Distinct Records in SQL →

I have previously posted about the SQL MERGE statement, and how powerful it is here: https://blog.jooq.org/arcane-magic-with-the-sql2003-merge-statement/ Unfortunately, not all databases support this statement. Also, very often it is quite a bit of overkill, when what you want to do is to simply INSERT or UPDATE a single record, depending on whether it already exists. MySQL's … Continue reading How to simulate MySQL’s INSERT statement extensions →

As I'm mostly using Oracle for work projects, the concept of the DUAL dummy table has become quite intuitive. I hardly ever think about the days when I was playing around with that table to find out its purpose (e.g. writing into it when DUAL was still a physical object, and thus killing the whole … Continue reading SQL Trouble with dummy tables →