FIrst of all, kudos to Tim Hall. This is one of the great times of the year when all these thankful blogs are posted in a day. If you read nothing else in the blogs all year, picking some of them would not be a bad choice.
Speaking of which, I will talk about being thankful for blogs in general. No, not about the new ones explaining all the new features we get in new versions. While that is very fascinating and motivates me to play with new tech, it is not the great thing with blogs.
What I think is great with blogs is old blogs. Yes, there may be few things as unsexy as old forgotten blog posts.
When there is an issue to resolve or a concept to get up to speed on, there are few things better than the blogs written a year or ten ago. But are not everyone experts on everything when some time has passed. Nope, not even one person is a specialist on every facet of Oracle database technology.
Sometimes it is one thing one knows fairly well but needs a to understand edge cases, experiences, when not to use and so forth. Then a short google session generates a reading list as good as any book.
A few examples of blogs I have stumbled on that was not published this year but that provided great information and input follows. They are just things from the top of my mind when thinking back about such blogs.
Tobias Arnhold wrote about views provided by APEX. It shows a SQL listing all the views and shows the views hierarchical relationship. Not only was that useful, but a side effect was that I realized this was available as well as that the relationship could be found in metadata. It is a post over six years old, often thought of long forgotten. Still very applicable. In fact, Tobias may even have forgotten the post himself, it is even more applicable today as there have been a lot of views added to the ones available back in 2012,
Another great one is Connor McDonalds –@connor_mc_d –post from early 2016 on auditing row changes. It is a great collection of all the things provided to you to avoid auditing columns, tables, triggers and so forth. Including a complete test case and demo from start to finish. Still two years old, but when needed it is a great start.
Then there are of course classics like Toon Koppelaars blog The Helsinki Declaration (IT-Version) that starts with the IT-version of it. If you have not read the four posts it consists of, you owe it to yourself to do so. Go back to the beginning. It should be mandatory reading for how to build database intensive applications.
I leave it at those to not extend this post more than necessary. But it shows the value of the combined effort of the community to write down small and big things as we come across them. There is immense value in those posts long after they have been written. Some are even more valuable a few years later when the world and the technology has matured enough to make it mainstream.