A very busy lecture this week with Manoj introducing some index structures including:
- B – Tree – Normalized but inconsistent lookup times.
- B+ Tree – Normalized, all keys in leaf nodes. Used by Oracle.
Most of the lecture was focussed on the above index structures, however we did move onto quickly cover Oracle Clusters (used to make efficient physical storage of regularly joined tables) and the Oracle Data Dictionary
Finally we tried to get through a short Advanced SQL lecutre but ended up running a bit short on time to review the more complex commands:
- Outer Joins
- Correleated Subqueries
- EXISTS predicate
Pearl of the Week: Practice SQL.