2.2 Tuning to Avoid Key Lookups and Residual Predicates

Key lookups have a bad reputation, but most of them really aren’t that bad – especially when we consider the alternatives, trying to get the developers to select less columns, or building huge covering indexes. However, there’s one kind of key lookup we do need to fix, and it’s easy: the residual predicate.

To access this incredible, amazing content, you gotta get Live Class Season Pass, Mastering Index Tuning or Recorded Class Season Pass, or log in if you already shelled out the cash.

Key lookups have a bad reputation, but most of them really aren’t that bad – especially when we consider the alternatives, trying to get the developers to select less columns, or building huge covering indexes. However, there’s one kind of key lookup we do need to fix, and it’s easy: the residual predicate.
To access this incredible, amazing content, you gotta get Live Class Season Pass, Mastering Index Tuning or Recorded Class Season Pass, or log in if you already shelled out the cash.
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