SQL
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Software Development
SQL: Counting Groups of Rows Sharing Common Column Values
In this post, I focus on using simple SQL SELECT statements to count the number of rows in a table…
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Software Development
jOOQ Tuesdays: Glenn Paulley Gives Insight into SQL’s History
Welcome to the jOOQ Tuesdays series. In this series, we’ll publish an article on the third Tuesday every other month…
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Software Development
How to Evolve from RDBMS to NoSQL + SQL
For the past 25 years, applications have been built using an RDBMS with a predefined schema that forces data to…
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Software Development
How to Detect Slow Queries with jOOQ
Just now, we implemented a nice little feature in jOOQ’s code generator: https://github.com/jOOQ/jOOQ/issues/4974 It detects whenever the jOOQ code generator…
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Software Development
Impress Your Coworkers by Using SQL UNPIVOT!
I’ve recently encountered a very interesting question on Stack Overflow by an unnamed user. The question was about generating a…
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Software Development
Oracle LONG and LONG RAW Causing “Stream has already been closed” Exception
Like many old databases, Oracle has legacy data types, which are rather nasty to work with in every day SQL.…
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Software Development
How to Fill Sparse Data With the Previous Non-Empty Value in SQL
The following is a very common problem in all data related technologies and we’re going to look into two very…
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Software Development
SQL GROUP BY and Functional Dependencies: A Very Useful Feature
Relational databases define the term “Functional Dependency” as such (from Wikipedia): In relational database theory, a functional dependency is a…
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Software Development
How to Find the Longest Consecutive Series of Events in SQL
A very interesting problem that can be solved very easily with SQL is to find consecutive series of events in…
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