Win Surprise Gifts!!!
Top 5 Contributors of the Month
Post New Question
Subscribe to Interview Questions
Database:What is Unique key?
Posted By :
Posted Date :
July 28, 2011
Unique key also ensures the uniqueness of the column values but also it creates a non clustured index.
You can also find related Interview Question to
Database:What is Unique key?
You work for a bank that uses a SQL Server 2005 database to store line items from customer banking transactions. The bank processes 50,000 transactions every day. The application requires a clustered index on the TransactionID column. You need to create a
table that supports an efficient reporting solution that queries the transactions by date.What are the two ways to achieve this goal? (Each correct answer presents a complete solution. Choose two.)
A. Place a nonclustered index on the date column.
B. Add a unique clustered index on the date column
C. Map each partition to a filegroup, with each filegroup accessing a different physical
D. Create a partitioning scheme that partitions the data by date.
Database Concurrency in Sql Server.
When two or more user try to update same type of data in a table then Database Concurrency helps in this situation.
There are 2 types of Database Concurrency
Pessimistic: When one user try to change the data with pessimistic concurrency then a lock is placed on the data in a table so that another user cannot change data. when one user finishes then other user can able to change.
Optimistic: When two user works on the same data in a table and one change that data first then second user cannot change that same data becasue the which he have using is allready changed so he cannot do the change becasue change apply to another data that is changed by first user.
What is the .NET that allows the retrieval of data by a unique key?
HashTable is the .NET collection class that allows the retrieval of data by a unique key
Which is the subset of SQL commands used to manipulate Oracle Database structures, including tables?
Data Definition Language (DDL)
What is a Database system?
The database and DBMS software together is called as Database system.
Unique Key constraint
1) UNIQUE constraints are to make sure that no duplicate values are entered in specific columns that do not participate in a primary key.
2) When you are placing an unique constraint it will automatically create Unique Index to maintain the integrity.
3) Unique Allows one Null value per column where as Primary key doesn't allow null values.
4) There is no limit on having number of unqiue constraints on a table.
5) Unique Key constraint can be referenced in Foreign Key Column.
Can SharePoint be linked to a SQL database?
This is possible via a custom application, but it not natively supported by SharePoint or SQLServer.
Best Method to retrieve two values from Database (SQL Server)
ExecuteNonQuery() using Output parameter.
How many Files per database will accept?
32,767 files are the maximum number in SQL Server 2005
Is it possible to create Cluster Index on Unique Key Column?
Unique key column by default creates a non-cluster index on the column. Primary key creates cluster index on the column. The only difference is Unique key column allows only one null value. So is it possible to have cluster index on Unique key column?
The answer is YES. Though Unique key allows null value but it still maintains the uniqueness of the column.
What's the .NET collection class that allows an element to be accessed using a unique key?
Which of the following database design features is most important to SQL performance?
The introduction of data redundancy
Where is Cache data stored-in memory, on the hard disk, in a database, or on a state server?
The Cache object is stored in memory.
Name of the command to view the current amount of free (unallocated) space in the database in SQL Server?
Name of command is :sp_spaceused
This command displays the database_size in MB, and it's also shows unallocated space for the database.
Quick Links For Interview Questions Categories:
Find questions, FAQ's and their answers related to .NET, C#, Vb.Net, Sql Server and many more.
Now you can find lots of .NET, C#, Vb.Net, SQL Server,Windows, ASP.Net related Questions and their Answers here at www.dotnetspark.com. Our aim is to help you pass your certification Exams (MCP, MCSD, MCAD etc.,) with flying scores and get good name in your company.
So, Start looking our
section daily and improve your .NET Skills. You can also help others by posting Interview Questions and their Answers in this section.
Hall of Fame
Terms of Service
Tell A Friend