Lesson 06.3
Indexing (B-tree, hash)
An index is an extra data structure that helps a database find rows without scanning the whole table; B-trees preserve order for ranges, while hash indexes specialize in equality lookups.
Find one order number
Ava enters one order number. The computer should not read every cookie order to find it.
In this lesson you'll
- 1Follow one run and learn how to read the picture
- 2Predict what changes before revealing the result
- 3Compare the choices and help Ava get one matching order without too much waiting