- World's Largest Collection of Interview Questions & Answers, FAQs, queries, sample papers, exam papers, dumps, what, why, how, where, when questions - Testing EBooks, Tutorials, Articles, Jobs, Training Institutes etc. - Gate EBooks, Tutorials, Articles, FAQs, Jobs, Training Institutes etc. - MBA EBooks, Tutorials, Articles, FAQs, Jobs, Training Institutes etc. - IAS EBooks, Tutorials, Articles, FAQs, Jobs, Training Institutes etc. - SAP EBooks, Tutorials, Articles, FAQs, Jobs, Training Institutes etc. - of GRE EBooks, Tutorials, Articles, FAQs, Jobs, Training Institutes etc.

Sponsored Links

Interview Questions
Our Services

Question :

What is a transaction isolation level and What is the advantage of it? What are different options that we set for a transaction isolation level? Transaction isolation levels are used when we go for transactions in stored procedures used in Transact SQL.

Category SQL Server Interview Questions
Rating (4.1) By 8 users
Added on 4/3/2013
Views 444
Rate it!



Transaction Lavel isolation:- The isolation level used during the execution of SQL statements determines the degree to which the activation group is isolated from concurrently executing activation groups.

Thus, when activation group P executes an SQL statement, the isolation level determines:

* The degree to which rows retrieved by P and database changes made by P are available to other concurrently executing activation groups.
* The degree to which database changes made by concurrently executing activation groups can affect P.

There are many advantages to this approach: read-intensive applications typically want more index structures, data redundancies, and even other views of data. Transaction processing systems want the best write throughput while incurring only the most minimal overhead. The access patterns of readers and writers typically differ: Readers are more prone to larger analysis types of queries, and writers are more prone to singleton inserts, updates, and deletes. When these activities are separated, the administrator can focus on recovery strategies for a smaller, more manageable transaction processing system. OLTP databases tend to be much smaller than data redundant decision-support or analysis-oriented databases.

There are four isolation levels:


1. Read uncommitted
When it's used, SQL Server not issue shared locks while reading data. So, you can read an uncommitted transaction that might get rolled back later. This isolation level is also called dirty read. This is the lowest isolation level. It ensures only that a physically corrupt data will not be read.

2.Read committed
This is the default isolation level in SQL Server. When it's used, SQL Server will use shared locks while reading data. It ensures that a physically corrupt data will not be read and will never read data that another application has changed and not yet committed, but it does not ensure that the data will not be changed before the end of the transaction.

3.Repeatable read
When it's used, the dirty reads and nonrepeatable reads cannot occur. It means that locks will be placed on all data that is used in a query, and another transactions cannot update the data.

Most restrictive isolation level. When it's used, then phantom values cannot occur. It prevents other users from updating or inserting rows into the data set until the transaction is complete.

If you have the better answer, then send it to us. We will display your answer after the approval.
Rules to Post Answers in
  • There should not be any Spelling Mistakes.
  • There should not be any Gramatical Errors.
  • Answers must not contain any bad words.
  • Answers should not be the repeat of same answer, already approved.
  • Answer should be complete in itself.
Name :*
Email Id :*
Answer :*
Verification Code Code Image - Please contact webmaster if you have problems seeing this image code Not readable? Load New Code
Process Verification Enter the above shown code: *
Inform me about updated answers to this question

Related Questions
View Answer
What is the difference between the full, simple and bulk log recovery models?
View Answer
What does the Log Reader agent in SQL Server 2005 replication do?
View Answer
What does this return?
select (1324 & 1024)
View Answer
Where does Profiler store its temporary data in SQL Server 2005?
View Answer
What does this return?
declare @i int
select @i = -5
select +@i
View Answer
Which of the following modules within SQL Server 2005 cannot be signed with a digital signature?
View Answer
What are the three possible functions of the plus (+) operator in SQL Server 2005, the base installed T-SQL?
View Answer
What does the Queue Reader Agent do in SQL Server 2005 replication?
View Answer
How does a differential backup know which extents have changed so that it can be very quickly run?
View Answer
When you create a new Message Type in the SQL Server 2005 Service Broker, what does the Authorization parameter signify?
View Answer
What is the recommended way to send mail from SQLAgent in SQL Server 2005?
View Answer
How do I submit a form or a part of a form without a page refresh?
View Answer
In which order do you perform an upgrade to SQL Server 2005 for replicated databases?
View Answer
Error severity 13 indicates what?
View Answer
What is SQL Server ?
View Answer

Please Note: We keep on updating better answers to this site. In case you are looking for Jobs, Pls Click Here - Best Freshers & Experienced Jobs Website.

View ALL SQL Server Interview Questions & Answers

User Options
India News Network

Latest 20 Questions
What is meant by Proactive, Retroactive and Simultaneous Update.
What is cold backup and hot backup (in case of Oracle)?
What are cursors give different types of cursors?
What are stand-alone procedures?
What is Authorization and Integrity manager?
What is Transaction Manager?
What is Storage Manager?
What are stored-procedures? And what are the advantages of using them?
What is database Trigger?
Name the three major set of files on disk that compose a database in Oracle.
How do you communicate with an RDBMS
What is the job of the information stored in data-dictionary?
Name the sub-systems of a RDBMS.
What are the primitive operations common to all record management systems?
What do you mean by Correlated subquery?
What is a query?
What is "transparent DBMS"?
What do you mean by flat file database?
What are the different phases of transaction?

Fresher Jobs | Experienced Jobs | Government Jobs | Walkin Jobs | Company Profiles | Interview Questions | Placement Papers | Companies In India | Consultants In India | Colleges In India | Exams In India | Latest Results | Notifications In India | Call Centers In India | Training Institutes In India | Job Communities In India | Courses In India | Jobs by Keyskills | Jobs by Functional Areas

Testing Articles | Testing Books | Testing Certifications | Testing FAQs | Testing Downloads | Testing Interview Questions | Testing Jobs | Testing Training Institutes

Gate Articles | Gate Books | Gate Colleges | Gate Downloads | Gate Faqs | Gate Jobs | Gate News | Gate Sample Papers | Gate Training Institutes

MBA Articles | MBA Books | MBA Case Studies | MBA Business Schools | MBA Current Affairs | MBA Downloads | MBA Events | MBA Notifications | MBA FAQs | MBA Jobs
MBA Job Consultants | MBA News | MBA Results | MBA Courses | MBA Sample Papers | MBA Interview Questions | MBA Training Institutes

GRE Articles | GRE Books | GRE Colleges | GRE Downloads | GRE Events | GRE FAQs | GRE News | GRE Training Institutes | GRE Sample Papers

IAS Articles | IAS Books | IAS Current Affairs | IAS Downloads | IAS Events | IAS FAQs | IAS News | IAS Notifications | IAS UPSC Jobs | IAS Previous Question Papers
IAS Results | IAS Sample Papers | IAS Interview Questions | IAS Training Institutes | IAS Toppers Interview

SAP Articles | SAP Books | SAP Certifications | SAP Companies | SAP Study Materials | SAP Events | SAP FAQs | SAP Jobs | SAP Job Consultants
SAP Links | SAP News | SAP Sample Papers | SAP Interview Questions | SAP Training Institutes |

Copyright ©2003-2016, All Rights Reserved.
Privacy Policy | Terms and Conditions

Cache = 0.015015 Seconds