Category Archives: Interview Questions

Interview Questions

Interview Questions On Sql Server -Part 2

Posted on January 31, 2010 by vivekjohari

1. What is the difference between the Union and Union All? 1) Union is used to select distinct data from the tables but Union All allows duplicate rows to be selected from the tables. 2) The second difference between Union … Continue reading →

Posted in Interview Questions | Tagged | 27 Comments

Interview Questions on sql server -Part-1

Posted on January 31, 2010 by vivekjohari

1. What is the Normalization? Normalization:-Normalization can be defined as the process of organization the data to reduce the redundant table data to the minimum. This process is carried out by dividing the database into two or more than two … Continue reading →

Posted in Interview Questions | Tagged | 24 Comments

Difference Between Having and Where Clause in Sql Server

Posted on January 31, 2010 by vivekjohari

Both Having Clause and Where clause is used to filter the data coming from the Select statement, but still there are some differences between them. These difference are given below:- To show the difference between the Where Clause and the … Continue reading →

Posted in Imp SQL Difference, Interview Questions, SQL Group By Having, SQL Server | Tagged | 39 Comments

How to find duplicate values in a table

Posted on January 31, 2010 by vivekjohari

Sometimes duplicate values in tables can create a major problem when we do not make a primary key or a unique key on a table. In these cases we need to find out the duplicate records and need to delete … Continue reading →

Posted in Interview Questions, SQL Basic Concepts, SQL Server | Tagged , | 33 Comments

Difference between Clustered Index and Non clustered Index

Posted on January 3, 2010 by vivekjohari

Indexes-Indexing  is way to sort and search records in the table. It will improve the speed of locating and retrieval of records from the table.It can be compared with the index which we use in the book to search a … Continue reading →

Posted in Imp SQL Difference, Interview Questions, SQL Indexes, SQL Server | Tagged , , | 31 Comments

Sql Server- Difference between Stored Procedure and Function

Posted on December 22, 2009 by vivekjohari

In Sql Server, both functions and stored procedures can be defined as the logically grouping of Sql statements formed to complete a task, but still there are many differences between Stored procedure and Functions. These differences can be summarized as … Continue reading →

Posted in Imp SQL Difference, Interview Questions, SQL Functions, SQL Server, SQL Stored Procedure | Tagged | 6 Comments

Difference between Delete and Truncate Command

Posted on December 17, 2009 by vivekjohari

Although the Delete and Truncate Commands logically does the same work of deleting the rows from the table but still there are many differences in their working. These differences are given below:- 1) Delete command maintained the logs files of … Continue reading →

Posted in Imp SQL Difference, Interview Questions, SQL Basic Concepts, SQL Server | Tagged | 1 Comment

Difference between Primary key and Unique key

Posted on October 5, 2009 by vivekjohari

var gaJsHost = ((“https:” == document.location.protocol) ? “https://ssl.” : “http://www.”); document.write(unescape(“%3Cscript src=’” + gaJsHost + “google-analytics.com/ga.js’ type=’text/javascript’%3E%3C/script%3E”)); try { var pageTracker = _gat._getTracker(“UA-11608194-1”); pageTracker._trackPageview(); } catch(err) {} Both Primary key and Unique key enforce uniqueness of the column on which … Continue reading →

Posted in Imp SQL Difference, Interview Questions, SQL Primary Key Constraint, SQL Server | Tagged | 30 Comments

Difference between Subquery, Nested Subquery and Correlated Subquery

Posted on September 29, 2009 by vivekjohari

Difference between Subquery, Nested Subquery and Correlated Subquery Query Query can be defined as a way to inquire the data from the database. It is used to extract the data from one table or multiple tables depending upon the user … Continue reading →

Posted in Interview Questions, Most Imp SQL Concepts, SQL Queries Sub-queries, SQL Server | Tagged , , | 102 Comments