It’s that time of the month again, when we have the T-SQL Tuesday blog party. This month we have a new host, Camilia Henrique with an invitation on advice you would give to your younger self, but in the area of T-SQL. That’s a good one, and it focuses on a technical skill that many data professionals need.
Participating in T-SQL Tuesday is a good way to practice your writing, your skills, and show your thoughts on some aspect of your job. Even if you miss the party one month, feel free to write a post later and link it to the main post on the T-SQL Tuesday site.
Practice, Practice, Practice
I learned SQL first as someone working with dBase, FoxPro, and Clipper. I moved to SQL Server and T-SQL later, with a basic grounding on how to query for simple sets of data, but I quickly learned performance can matter a lot.
As I’ve tried to keep up with the language, one of the things that has struck me is that T-SQL can be complex to structure because it’s relatively simple with few keywords. You can unintentionally create cross joins or row-by-row (RBAR) structures that perform poorly and waste resources on your system.
I’ve found that practicing with programming exercises and solving problems to be the best way to improve my skills. I don’t do it enough these days, and when I answer questions on SQLServerCentral, invariably one of the experts there will post a solution that performs better and I learn something new.
If I were talking to myself, I’d say to look more deeply into APPLY and the OVER() clause right now. Make sure you understand tally tables and their uses, and work through exercises like the Advent of Code, Exorcism, Project Euler, or something similar. Heck, just answer questions in a forum for yourself, with your own solution.
Learn how to create queries that can efficiently gather together, filter, and aggregate your data in ways that are helpful for clients without taxing server hardware. In the era of cloud computing and pay for data moved or data processed somehow, this is an invaluable skill.