Oracle SQL :Interview Questions
1).What is the difference between a view and a synonym ?
1).What is the difference between a view and a synonym ?
- Synonym is just a second name of table used for multiple link of database.
- View can be created with many tables, and with virtual columns and with conditions.
- But synonym can be on view.
2)What is the difference between alias and synonym ?
A)Alias is temporary and used with one query. Synonym is permanent and not used as alias.
3)Can database trigger written on synonym of a table and if it can be then what would be the effect if original table is accessed.
A) Yes, database trigger would fire.
4)What is the result of the following SQL :
Select 1 from dual
UNION
Select 'A' from dual;
A)Will throw error
5)Can you create index on view
No.
4)What is the result of the following SQL :
Select 1 from dual
UNION
Select 'A' from dual;
A)Will throw error
5)Can you create index on view
No.