Erik Darling continues a series on understanding execution plans. First up, what some of those warnings mean:
The good news is that SQL Server’s query plans will attempt to warn you about problems. The bad news is that most of the warnings only show up in Actual Execution Plans. The worse news is that a lot of the warnings that try to be helpful in Estimated Execution plans can be pretty misleading.
Next, Erik reviews some interesting properties:
There’s a lot of stuff flying around in a query plan. Data and what not.
Sure, you can hover over operators and arrows and see some stuff, but if you really wanna see stuff — I mean REALLY wanna see stuff — you gotta get into the properties.
Check out both posts.