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October 4, 2016

10/04/2016 02:33:00 AM

Oracle SQL Interview Questions

ebiztechnics Oracle APPS interview questions
1. How will you a activate/deactivate integrity constraints ?
 
The  integrity constraints can be enabled or disabled by ALTER TABLE ENABLE constraint/DISABLE constraint.
 
2. If an unique key constraint on DATE column is created, will it validate the rows that are inserted with SYSDATE ?
 
It won't, Because SYSDATE format contains time attached with it.
 
3. What is a database link ?
 
Database  Link  is  a  named  path  through  which a remote database can be accessed.
 
4.  How to access the current value and next value from a sequence ? Is it possible  to  access  the  current value in a session before accessing next value ?
 
Sequence name CURRVAL, Sequence name NEXTVAL.
 
It  is  not possible. Only if you access next value in the session, current value can be accessed.
 
5. What is CYCLE/NO CYCLE in a Sequence ?
 
CYCLE  specifies  that  the  sequence  continues  to  generate values after reaching  either  maximum   or  minimum value. After pan ascending sequence reaches  its  maximum  value,  it  generates  its  minimum  value.  After a descending sequence reaches its minimum, it generates its maximum.
 
NO  CYCLE  specifies  that   the  sequence cannot generate more values after reaching its maximum or minimum value.
 
6. What are the advantages of  VIEW ?
 
To protect some of the columns of a table from other users.
To hide complexity of a query.
To hide complexity of calculations.
 
7. Can a view be updated/inserted/deleted? If Yes under what conditions ?
 
A View can be updated/deleted/inserted if it has only one base table if the view  is  based  on columns from one or more tables then insert, update and delete is not possible.
 
8.If  a  View  on  a  single base table is manipulated will the changes be reflected on the base table ?
 
If  changes are made to the tables which are base tables of a view will the changes be reference on the view