Oracle DBA interview questions 2016

Oracle DBA interview questions 2016.

Oracle Concepts and Architecture
Database Structures
1. What are the components of physical database structure of Oracle database?
Oracle database is comprised of three types of files. One or more datafiles, two are more
redo log files, and one or more control files.
2. What are the components of logical database structure of Oracle database?
There are tablespaces and database’s schema objects.
3. What is a tablespace?
A database is divided into Logical Storage Unit called tablespaces. A tablespace is used to
grouped related logical structures together.
4. What is SYSTEM tablespace and when is it created?
Every Oracle database contains a tablespace named SYSTEM, which is automatically
created when the database is created. The SYSTEM tablespace always contains the data
dictionary tables for the entire database.
5. Explain the relationship among database, tablespace and data file.
Each databases logically divided into one or more tablespaces one or more data files are
explicitly created for each tablespace.
6. What is schema?
A schema is collection of database objects of a user.
7. What are Schema Objects?
Schema objects are the logical structures that directly refer to the database’s data. Schema
objects include tables, views, sequences, synonyms, indexes, clusters, database triggers,
procedures, functions packages and database links.
8. Can objects of the same schema reside in different table spaces?
Yes.
9. Can a tablespace hold objects from different schemes?
Yes.
10. What is Oracle table?
A table is the basic unit of data storage in an Oracle database. The tables of a database
hold all of the user accessible data. Table data is stored in rows and columns.
11. What is an Oracle view?
A view is a virtual table. Every view has a query attached to it. (The query is a SELECT
statement that identifies the columns and rows of the table(s) the view uses.)
12. Do a view contain data?
Views do not contain or store data.