Physical Data Warehouse Design - Data Warehouse Systems: Design and Implementation - page 275

7.3 What is view maintenance? What is incremental view maintenance?
7.4 Discuss the kinds of algorithms for incremental view maintenance, that
is, using full and partial information.
7.5 Define self-maintainable aggregate functions. What is a self-
maintainable view?
7.6 Explain briefly the main idea of the summary-delta algorithm for data
cube maintenance.
7.7 How is data cube computation optimized? What are the kinds of
optimizations that algorithms are based on?
7.8 Explain the idea of the PipeSort algorithm.
7.9 How can we estimate the size of a data cube?
7.10 Explain the algorithm for selecting a set of views to materialize. Discuss
its limitations. How can they be overridden?
7.11 Compare B-tree + indexes, hash indexes, bitmap indexes, and join
indexes with respect to their use in databases and data warehouses.
7.12 How do we use bitmap indexes for range queries?
7.13 Explain run length encoding.
7.14 Describe a typical indexing scheme in a star and snowflake schemas.
7.15 How are bitmap indexes used during query processing?
7.16 How do join indexes work in query processing? For which kinds of
queries are they ecient? For which kinds of queries are they not
ecient?
7.17 What is partitioning? Which kinds of partitioning schemes do you
know?
7.18 What are the main advantages and disadvantages of partitioning?
7.19 Discuss the characteristics of storage modes in Analysis Services.
7.20 How do indexed views compare with materialized views?
7.14 Exercises
7.1 In the Northwind database, consider the relations
Employee(EmplID, FirstName, LastName, Title, . . . )
Orders(OrderID, CustID, EmpID, OrderDate, . . . ).
Consider further a view
EmpOrders(EmpID, Name, OrderID, OrderDate)
computed from the full outer join of tables Employee and Orders ,where
Name is obtained by concatenating FirstName and LastName .
Define the view EmpOrders in SQL. Show an example of instances
for the relations and the corresponding view. By means of examples,
show how the view EmpOrders must be modified upon insertions and
deletions in table Employee . Give the SQL command to compute the