To provide all the details about example: this book table of contents can be seen at
http://shop.oreilly.com/product/9780596009762.do
In .epub the hierarchy is deeper - there are subsections like „Problem”, „Solution”, „Oracle notes”, „DB2 notes”... in every section. Many tech books have similar structure.
So on Sony I see
1 Retrieving Records
2 Sorting Query Results
3 Working with Multiple Tables
4 Inserting, Updating, Deleting
(... up to 14 ...)
expanding chapter 4 gives
Inserting a New Record
Inserting Default Values
Overriding a Default Value with NULL
Copying Rows from One Table into Another
Copying a Table Definition
Inserting into Multiple Tables at Once
Blocking Inserts to Certain Columns
Modifying Records in a Table
(.. and a few more ...)
and so on.
On Kobo I get
1 Retrieving Records
Retrieving All Rows and Columns from a Table
Problem
Solution
Discussion
Retrieving a Subset of Rows from a Table
Problem
Solution
Discussion
Finding Rows That Satisfy Multiple Conditions
(and info that there are over hundred pages of toc)