Phil Parkin (9/27/2016)
Try to solve the various T-SQL problems that other people post here ... and compare your solutions with those written by others. You'll learn a lot if you take the time to understand how and why they did it the way they did.
Very much this. The best way to get better at writing T-SQL is to write a lot of T-SQL. You may not have much opportunity at work, so you have to find other places. Any time I'm learning new tech or expanding my skill set, I try really hard to find the questions related to that on the forums and attempt to provide answers. It's a great way to get better & learn.
Another thing to help you learn more is to teach. Set up a class at work where you're going to do a 15-20 minute lunch & learn. You can have a single topic or just two topics each day where you're going to share a little of what you're working on with your co-workers. They can also bring stuff to the table.
"The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood"
- Theodore Roosevelt
Author of:
SQL Server Execution Plans
SQL Server Query Performance Tuning