Primary Key vs Unique Key
Primary Key creates a clustured Index on a table when it is createdUnique Key creates a non-clustured Index on a table when it is created
Primary Key doesn't allow NULL values
Unique Key allows only one NULL value
Tuesday, May 24, 2005
About Me
- Name: Chandra Ananthapatnayakuni
- Location: Hyderabad, Andhra Pradesh, India
I did my Engineering in Computer Science and Engineering from (Vellore Engineering College) Madras University in 1998. Since the Third year of my Engineering I was working on various Microsoft Technologies such as VB, VC++ and SQL Server. I have more than 8 years of IT experience My core areas of interest are Query Optimization and Performance Tuning. Presently I am working for Computer Sciences Corporation, Hyderabad. Prior to CSC I worked for Wipro and IBM Global Services, Bangalore. I actively participate in Microsoft SQL Server Newsgroups and User groups from Hyderabad and Bangalore I am founder and publisher of my site www.sqlresource.com, which I just started working on. You can find my blogs on http://chanduas.blogspot.com/
Links
Previous Posts
- Maximum Capacity Specifications
- SQL Server 2000 Resource Kit
- Change owner of the database
- Error Handling in SQL Server
- Remove Spaces - TRIM
- Editions of SQL Server 2000
- Find the Version of SQL Server
- Enable or Disable a Constraint
- Rename user-created objects in SQL Server
- List Available Databases
1 Comments:
Hi:
i feel u r 1st statement is not correct(its not mandatory to create clustered index while creating PK).Clustered index need not be a primary key.u can check the same in enterprise manager.
Post a Comment
<< Home