Review Questions

1.	The data dictionary view IND has the same definition as what other data dictionary view?
2.	The most common form of a table in the Oracle database is a(n) table.
3.	What clause do you add to the CREATE TABLE statement to create a temporary table?
4.	What tables are displayed if a user accesses the ALL_TABLES data dictionary view?
5.	Name two ways in which external tables are different from relational tables.
6.	True or false: Oracle resolves object references by checking for private synonyms first.
7.	What are two reasons for creating a view against one or more tables?
8.	What database object type can be used to generate a series of sequential numbers?
9.	True or false: Data dictionary tables retain their contents even after the database has been shut down and restarted.
10.	An index created on more than one column is known as what kind of index?

Answers

1.	The data dictionary view IND is equivalent to the data dictionary view USER_INDEXES.
2.	Relational
3.	You add the clause GLOBAL TEMPORARY to the CREATE TABLE statement to create a temporary table.
4.	The ALL_TABLES data dictionary view contains a row for each table in the user’s schema plus a row for each table that the user has access to in other schemas of the database.
5.	External tables cannot be updated, and external tables cannot have indexes created on them.
6.	False, Oracle resolves object references by checking for a real object owned by the user, then checks for a private synonym, and then checks for a public synonym.
7.	A view can be created to hide the complexity of a table join from the user. A view can also be created to restrict the rows or columns seen by users of the view.
8.	A sequence can be used to generate a series of sequential numbers.
9.	True, data dictionary tables retain their contents even after the database has been restarted. Dynamic performance views, however, lose their contents when the database is shut down and restarted.
10.	An index based on more than one column is known as a composite index.