SQL Server Difference Between Questions List-2

1. Difference beteen @@identity scopeidentity
2. Difference between ISQL and OSQL
3. Difference between data replication and data backup
4. Difference between group by and order by
5. Difference between count(*) and count(1)
6. Difference between normalization and denormalization
7. Difference between non-relational database system and relational database system
8. Difference between PRIMARY KEY and UNIQUE KEY with NOT NULL constraint
9. Difference between stored procedure transformation and external procedure transformation
10. Difference between delete,drop and truncate in SQL Server
11. Difference between Candidate key and Foreign key
12. Difference between Inner join and Outer join
13. Difference between NULL and ISNULL in SQL Server 2008
14. Differences between Crystal Reports and SQL Server Reporting Services
15. Differences between INNER JOIN, LEFT JOIN and RIGHT JOIN in SQL Server