Nicely done and much more in-depth than I expected.
I generally find that I don't need to spend much time dealing deeply with query planners, low hanging fruit is quite easy enough to find in the enterprise db world (what, no index . . . bad hacker). I also have the advantage of working primarily in a batch oriented world, where my big data moves are simple nightly jobs. On a good day, I get to hack hierarchical data in a relational model and even blow the dust of boolean logic to do cool if . . then and case logic in the where clause of a SQL query. Good times.
But remembering the simple fact that you can see an access plan generated by the RDBMs of your choice will provide you many "heroic" opportunities when some random application blows up. Add them to your general toolbox along with a generous dose of decent SQL (Celko's books have worked for me) background.
I generally find that I don't need to spend much time dealing deeply with query planners, low hanging fruit is quite easy enough to find in the enterprise db world (what, no index . . . bad hacker). I also have the advantage of working primarily in a batch oriented world, where my big data moves are simple nightly jobs. On a good day, I get to hack hierarchical data in a relational model and even blow the dust of boolean logic to do cool if . . then and case logic in the where clause of a SQL query. Good times.
But remembering the simple fact that you can see an access plan generated by the RDBMs of your choice will provide you many "heroic" opportunities when some random application blows up. Add them to your general toolbox along with a generous dose of decent SQL (Celko's books have worked for me) background.