Read ALL chapters in textbook [chapters 11-20 in Complete book]
Except the following optional material:

Sections 2.6.4, 2.6.5 [11.7.4, 11.7.5]
Sections 5.3.3, 5.3.4, 5.3.5, 5.3.6 [14.3.6, 14.3.7, 14.3.8]
Sections 5.4.2, 5.4.3, 5.4.4 [14.4.2, 14.4.3, 14.4.4]
Sections 6.8.3, 6.9, 6.10  [15.7, 15.8, 15.9]
Sections 7.6, 7.7 [16.6, 16.7]
In Chapters 6, 7 [15, 16]: material on duplicate elimination operator, grouping, aggregation operators
Section 9.8 [11.8]
Sections 10.4, 10.5, 10.6, 10.7 [19.4, 19.5, 19.6, 19.7]