• +91 9971497814
  • info@interviewmaterial.com

Oracle Interview Questions Answers

Question 1 : Differentiate simple and complex, snapshots ?

Answer 1 : - A simple snapshot is based on a query that does not contains GROUP BY clauses, CONNECT BY clauses, JOINs, sub-query or snashot of operations. - A complex snapshots contain atleast any one of the above.

Question 2 : What are synonyms used for?

Answer 2 : - Mask the real name and owner of an object. - Provide public access to an object - Provide location transparency for tables, views or program units of a remote database. - Simplify the SQL statements for database users.

Question 3 : What are the advantages of views?

Answer 3 : - Provide an additional level of table security, by restricting access to a predetermined set of rows and columns of a table. - Hide data complexity. - Simplify commands for the user. - Present the data in a different perspective from that of the base table. - Store complex queries.

Question 4 : How can we reduce the network traffic?

Answer 4 : - Replication of data in distributed environment. - Using snapshots to replicate data. - Using remote procedure calls.

Question 5 : What is Index Cluster ?

Answer 5 : A Cluster with an index on the Cluster Key

Question 6 : What is difference between UNIQUE constraint and PRIMARY KEY constraint ?

Answer 6 : A column defined as UNIQUE can contain Nulls while a column defined as PRIMARY KEY can't contain Nulls.

Question 7 : What does a Control file Contain ?

Answer 7 : A Control file records the physical structure of the database. It contains the following information. Database Name Names and locations of a database's files and redolog files. Time stamp of database creation.

Question 8 : How to define Data Block size ?

Answer 8 : A data block size is specified for each ORACLE database when the database is created. A database users and allocated free database space in ORACLE data blocks. Block size is specified in INIT.ORA file and can’t be changed latter.

Question 9 : What are the Characteristics of Data Files ?

Answer 9 : A data file can be associated with only one database. Once created a data file can't change size. One or more data files form a logical unit of database storage called a tablespace.

Question 10 : What is Rollback Segment ?

Answer 10 : A Database contains one or more Rollback Segments to temporarily store "undo" information.

Oracle Contributors


Share your email for latest updates


Our partners