Friday, January 28, 2011

15 important SQL Server interview questions on Data Warehousing/Data Mining - Part 3

15 important SQL Server interview questions on Data Warehousing/Data Mining - Part 3


This section is Part 3 and it will cover the most asked SQL Server interview questions by the interviewer so have a look on the following and do revise it when ever you go for the SQL Server
interview

Normally SQL Server interview starts with.....
What is MODEL is Data mining world?

How are models actually derived?
What is a Decision Tree Algorithm?
Can decision tree be implemented using SQL?
What is Naïve Bayes Algorithm?
Explain clustering algorithm?
Explain in detail Neural Networks?
What is Back propagation in Neural Networks?
What is Time Series algorithm in data mining?
Explain Association algorithm in Data mining?
What is Sequence clustering algorithm?
What are algorithms provided by Microsoft in SQL Server?
How does data mining and data warehousing work together?
What is XMLA?
What is Discover and Execute in XMLA?

16 important SQL Server interview questions on Data Warehousing/Data Mining - Part 2

16 important SQL Server interview questions on Data Warehousing/Data Mining - Part 2


This section is Part 2 and it will cover the most asked SQL Server interview questions by the interviewer so have a look on the following and do revise it when ever you go for the SQL Server interview
Normally SQL Server interview starts with.....
What is an OLTP (Online Transaction Processing) System?
What is an OLAP (On-line Analytical processing) system?
What is Conceptual, Logical and Physical model?
What is Data purging?
What is Analysis Services?
What are CUBES?
What are the primary ways to store data in OLAP?
What is META DATA information in Data warehousing projects?
What is multi-dimensional analysis?
What is MDX?
How did you plan your Data warehouse project?
What are different deliverables according to phases?
Can you explain how analysis service works?
What are the different problems that “Data mining” can solve?
What are different stages of “Data mining”?
What is Discrete and Continuous data in Data mining world?

Monday, January 24, 2011

Debugging, Tracing and Instrumentation in .NET and ASP.NET (14 FAQ)

Debugging, Tracing and Instrumentation in .NET and ASP.NET (14 FAQ)


Contents



So, what’s the agenda?


Diagnosing a software application is an art and this art has to be more skillful when you go on production.

In development environment you have the complete VS IDE tool so the diagnosing becomes much easier. On production environment as a best practice you do not install visual studio IDE. So on production it’s like fighting with the lion without a knife.



This article has a three point agenda.
• We will first start with understanding some basic vocabularies like debug, trace and instrumentation.

• Once we understand the vocabularies we will see how to use the trace attribute to tracing in ASP.NET. We will also understand some drawbacks of the same.

• We will then try to remove those drawbacks using the full tracing framework which comes as a part of “system.diagnostic” namespace. In tracing framework we will try to understand trace object , switches and listeners.


You can watch my .NET interview questions videos on various sections like WCF, Silver light, LINQ, WPF, Design patterns, Entity framework etc.


What is Instrumentation?

Debugging application is not just about pressing F 10 or F 11 and watching “add watch windows” using visual studio IDE. Debugging becomes pretty complex on production environments where the project is deployed in a release mode and you need to figure out till what point the code ran and when did it crash. The worst part is you are enjoying your sleep at home and suddenly someone calls up and says, “Hey! the application crashed in production”.

If your application is well planned with proper instrumentation you can just say the person to view the event viewer or a log file for further details and you can give the solution on the phone itself.

So defining instrumentation in short, it’s the ability of the application to monitor execution path at critical points to do debugging and measure performance.



What is debugging and tracing?


We would like to enable application instrumentation in two situations while you are doing development and while your application is in production. When you monitor application execution and performance in development stage is termed as “Debugging” and when you do in deployed environment it’s termed as ‘Tracing’.

How can we implement debugging and tracing in ASP.NET ?

Debugging and tracing can be implemented by importing ‘System.Diagnostic’ namespace and by calling ‘Debug’and ‘Trace’ methods as shown in the below code. In the below code we are tracking critical execution points like page load and button click.


protected void Page_Load(object sender, EventArgs e)
{
Debug.Write("Debug :- The page is loaded\n");
Trace.Write("Trace :- The page is loaded\n");
}
protected void Button1_Click(object sender, EventArgs e)
{
Debug.Write("Debug :- Button is clicked\n");
Trace.Write("Trace :- Button is clicked\n");
}

How do we view the results of debug and trace?

As said previously debug is meant for enabling instrumentation in development phase while tracing helps during execution. During development VS IDE tool is the best medium of viewing debug information and during execution the mediums can be a browser, event viewers, file system etc.
In order to see debug information execute the project, click on debug, windows and click on output menu as shown in the below figure.


You should be able to see the output information in output windows as shown in the below figure.

As debug code is not shipped in production you will not be able to see the debug information while your application is go live. As said previously tracing information is seen when you execute the project in production mode or go live mode. Tracing information can be viewed by on various mediums:-

• By the user interface ( Web browser or the windows UI)

• Event viewer

• Log file, format can be XML, CSV etc.

• In ASP.NET you can also view by using Trace.axd

So can we see a quick sample of how tracing information can be viewed?

A quick and dirty way of seeing tracing information is by going to the ASPX front code and put trace=true in the ‘Page’ attribute.
<%@ Page Language="C#" AutoEventWireup="true" trace="true"
CodeBehind="Default.aspx.cs" Inherits="WebTracing._Default" %>

Once you have done the same you should be able to see tracing information as shown in the below figure. With trace enabled as true it also displays lot of other things like different page events , session data , hidden field data , http headers etc. I have circled the custom information which we have written using the ‘Trace’ object.



What if we want to enable tracing in all pages?

If you want to enable tracing in all pages, you need to enable trace in the ‘web.config’ file as shown in the below code snippet.

<system.web>
<trace enabled="true" pageOutput="true" requestLimit="40" localOnly="false"/>
</system.web>

Is it possible to do silent tracing, rather than displaying on the browser?

In actual production it will not be a good idea to enable the trace using the above two methodologies as the end user can view your tracing information on the browser. So the next logical question is how we silently trace the same.

In order to background silent tracing we need to go to the web.config file and in the trace tag enter pageoutput=false. By setting “pageoutput” to false we say the trace engines do not send messages to browser and collect them in memory.

<system.web>
<trace enabled="true" pageOutput="false" requestLimit="40"
localOnly="false"/>
</system.web>

This in memory stored instrumentation data can be viewed using Trace.axd by typing url http://localhost:2281/Trace.axd . Below is a sample screen shot which shows how the data looks. If you click on the view details you can see the tracing information.




How do I persist the instrumented information?


When we instrument using debug attribute either using page or AXD extension they are not persisted. In other words they are displayed on the browser temporarily.

Most of the times we would like to persist the information in a file, event viewer etc so that we can later see the history for proper diagnosis.
We need to enable the ‘writetoDiagnosticsTrace’ attribute to true. When this attribute is set to true the information is sent to a listener.

<trace enabled="true" requestLimit="10" localOnly="false"
writeToDiagnosticsTrace="true" pageOutput="false"/>

You can then define various types of listeners like text file listener, event viewer etc. Below is a sample code snippet of how the listeners actually look. So the ASP.NET tracing engine will emit diagnosis information which will be then caught and routed to the proper source by the listener.

<system.diagnostics>
<trace autoflush="true">
<listeners>
<clear/>
<add name="textwriterListener" type="System.Diagnostics.TextWriterTraceListener"
initializeData="c:\outfile.txt" traceOutputOptions="ProcessId, DateTime"/>
</listeners>
</trace>
</system.diagnostics>

Below is a simple snapshot of how instrumented data is captured.



There is too much noise can we only see information which we need?



When we use the trace attribute it emits out all the events of the page. Sometimes these events can hinder your diagnosis.

If you want to eliminate all ASP.NET events and just concentrate on your message then we need to add a source. We need to then write the messages on the source and the source will redirect the same to the trace listeners.

In order to define a source go to your web.config and in the “system.diagnostics’ tag enter the “source’ tag as shown in the below code snippet. In the below code snippet we have defined the source name as “myTraceSource”. Inside the source we can define variouslisteners.

<system.diagnostics>
<sources>
<source name="myTraceSource" switchName="mySwitch"
switchType="System.Diagnostics.SourceSwitch">
<listeners>
<!-… Define all your listeners in this place ..>
</listeners>
</source>
</sources>
</system.diagnostics>

Below is a complete sample code snippet with listeners defined inside the source.

<system.diagnostics>
<sources>
<source name="myTraceSource" switchName="mySwitch"
switchType="System.Diagnostics.SourceSwitch">
<listeners>
<clear/>
<add name="textwriterListener"
type="System.Diagnostics.TextWriterTraceListener"
initializeData="c:\outfile.txt" traceOutputOptions="ProcessId, DateTime"/>
</listeners>
</source>
</sources>
</system.diagnostics>

In order to send messages to the trace source using C# code first we need to import namespace “System.Diagnostics” as shown in the below code snippet.

using System.Diagnostics;
Once the namespace is imported we can then send messages on any event by creating the “TraceSource” object and calling “TraceEvent” as shown in the below code snippet.

TraceSource obj = new TraceSource("myTraceSource");
obj.TraceEvent(TraceEventType.Error, 0, "This is a error message");
obj.Close();


All the above methodologies are for web, how can we do tracing for windows?

It’s the same way define the source and listeners in your app.config file, create the tracesource object and call traceevent method to write the same to the listeners.


Can we emit different types of trace events like critical, warning, error etc?


We would like to emit different kind of messages from the application like critical messages, error message or just information. The types of messages can be defined by using “TraceEventType” enum as shown in the below code snippet.
obj.TraceEvent(TraceEventType.Critical, 0, "This is a critical message");
obj.TraceEvent(TraceEventType.Warning, 0, "This is a simple warning message");
obj.TraceEvent(TraceEventType.Error, 0, "This is a error message");
obj.TraceEvent(TraceEventType.Information, 0, "Simple information message");
obj.TraceEvent(TraceEventType.Verbose, 0, "Detail Verbose message");


Can we control what kind of information can be routed?




Sometime we would like to control the kind of diagnosis information we see. This can be achieved by using the switch tag in config file.

<system.diagnostics>
....
....
....
<switches>
<add name="mySwitch" value="1"/>
</switches>
</system.diagnostics>

You can define various values depending on what kind of diagnose information you want to record.




You can then attach the switch to the source.
<source name="myTraceSource" switchName="mySwitch"
switchType="System.Diagnostics.SourceSwitch">


How can switch off instrumentation?

Set the switch value to zero.

It would great if we can summarize?

Summarizing ASP.Net or windows application emits tracing information to the trace source; these messages can be controlled by switches and sent to various sources (file, event viewer, xml etc) which are defined using trace listeners. Below figure summarizes the complete
tracing framework visually.



References






Friday, January 21, 2011

14 important SQL Server interview questionson Data Warehousing/Data Mining - Part 1

14 important SQL Server interview questionson Data Warehousing/Data Mining - Part 1


This section is Part 1 and it will cover the most asked SQL Server interview questions by the
interviewer so have a look on the following and do revise it when ever you go for the SQL Server interview
Normally SQL Server interview starts with.....

What is “Data Warehousing”?
What are Data Marts?
What are Fact tables and Dimension Tables?
What is Snow Flake Schema design in database?
What is ETL process in Data warehousing?
How can we do ETL process in SQL Server?
What is “Data mining”?
Compare “Data mining” and “Data Warehousing”?
What is BCP?
How can we import and export using BCP utility?
During BCP we need to change the field position or eliminate some fields
how can we achieve this?

What is Bulk Insert?
What is DTS?
Can you brief about the Data warehouse project you worked on?

Thursday, January 20, 2011

16 important SQL Server interview questionson Service Broker - Part 2

16 important SQL Server interview questions on Service Broker - Part 2

This section is Part 2 and it will cover the most asked SQL Server interview questions by the
interviewer so have a look on the following and do revise it when ever you go for the SQL Server interview

Normally SQL Server interview starts with.....


What is XSL?
What is Element and attributes in XML?
Can we define a column as XML?
How do we specify the XML data type as typed or untyped?
How can we create the XSD schema?
How do I insert in to a table that has XSD schema attached to it?
What is maximum size for XML data type?
What is Xquery?
What are XML indexes?
What are secondary XML indexes?
What is FOR XML in SQL Server?
Can I use FOR XML to generate SCHEMA of a table and how?
What is the OPENXML statement in SQL Server?
I have huge XML file which we want to load in database?
How to call stored procedure using HTTP SOAP?
What is XMLA?

Wednesday, January 19, 2011

20 important SQL Server interview questionson Service Broker - Part 1

20 important SQL Server interview questionson Service Broker - Part 1


This section is Part 1 and it will cover the most asked SQL Server interview questions by the interviewer so have a look on the following and do revise it when ever you go for the SQL Server interview
Normally SQL Server interview starts with.....
What do we need Queues?
What is “Asynchronous” communication?
What is SQL Server Service broker?
What are the essential components of SQL Server Service broker?
What is the main purpose of having Conversation Group?
How to implement Service Broker?
How do we encrypt data between Dialogs?
What is XML?
What is the version information in XML?
What is ROOT element in XML?
If XML does not have closing tag will it work?
Is XML case sensitive?
What is the difference between XML and HTML?
Is XML meant to replace HTML?
Can you explain why your project needed XML?
What is DTD (Document Type definition)?
What is well formed XML?
What is a valid XML?
What is CDATA section in XML?
What is CSS?

Tuesday, January 18, 2011

20 important SQL Server interview questions on .NET integration - Part 3

20 importantSQL Server interview questions on .NET integration - Part 3



This section is Part 3 and it will cover the most asked SQL Server interview questions by the
interviewer so have a look on the following and do revise it when ever you go for the SQL Server interview
Normally SQL Server interview starts with.....

Can we have SQLCLR procedure input as array?
Can object data type be used in SQLCLR?
How is precision handled for decimal data types in .NET?
How do we define INPUT and OUTPUT parameters in SQLCLR?
Is it good to use .NET data types in SQLCLR?
How to move values from SQL to .NET data types?
What is SQLContext?
Can you explain essential steps to deploy SQLCLR?
How do create function in SQL Server using .NET?
How do we create trigger using .NET?
How to create User Define Functions using .NET?
How to create aggregates using .NET?
What is Asynchronous support in ADO.NET?
What is MARS support in ADO.NET?
What is SQLbulkcopy object in ADO.NET?
How to select range of rows using ADO.NET?
What are different types of triggers in SQl SERVER 2000?
INSTEAD OF triggers?
If we have multiple AFTER Triggers on table how can we define the sequence
of the triggers?

How can you raise custom errors from stored procedure?

26 important SQL Server interview questions on .NET integration - Part 2

26 important SQL Server interview questions on .NET integration - Part 2


This section is Part 2 and it will cover the most asked SQL Server interview questions by the
interviewer so have a look on the following and do revise it when ever you go for the SQL Server interview
Normally SQL Server interview starts with.....

What is Multi-tasking?
What is Multi-threading?
What is a Thread?
Can we have multiple threads in one App domain?
What is Non-preemptive threading?
What is pre-emptive threading?
Can you explain threading model in SQL Server?
How does .NET and SQL Server thread work?
How is exception in SQLCLR code handled?
Are all .NET libraries allowed in SQL Server?
What is “Hostprotectionattribute” in SQL Server 2005?
How many types of permission level are there for an assembly?
In order that an assembly gets loaded in SQL Server what type of checks
are done?

Can you name system tables for .NET assemblies?
Are two version of same assembly allowed in SQL Server?
How are changes made in assembly replicated?
In one of the projects following steps where done, will it work?
What does Alter assembly with unchecked data signify?
How do I drop an assembly?
Can we create SQLCLR using .NET framework 1.0?
While creating .NET UDF what checks should be done?
How do you define a function from the .NET assembly?
Can you compare between T-SQL and SQLCLR?
With respect to .NET is SQL SERVER case sensitive?
Does case sensitive rule apply for VB.NET?
Can nested classes be accessed in T-SQL?

Tuesday, January 11, 2011

21 important SQL Server interview questionson .NET integration - Part 1

21 important SQL Server interview questionson .NET integration - Part 1

This section is Part 1 and it will cover the most askedSQL Server interview questions by the interviewer so have a look on the following and do revise it when ever you go for the SQL Server interview
Normally SQL Server interview starts with.....


What are steps to load a .NET code in SQL SERVER 2005?
How can we drop an assembly from SQL SERVER?
Are changes made to assembly updated automatically in database?
Why do we need to drop assembly for updating changes?
How to see assemblies loaded in SQL Server?
I want to see which files are linked with which assemblies?
Does .NET CLR and SQL SERVER run in different process?
Does .NET controls SQL SERVER or is it vice-versa?
Is SQL CLR configured by default?
How to configure CLR for SQL SERVER?
Is .NET feature loaded by default in SQL Server?
How does SQL Server control .NET run-time?
In previous versions of .NET it was done via COM interface “ICorRuntimeHost”?
In .NET 2.0 it is done by “ICLRRuntimeHost”?
What is a “SAND BOX” in SQL Server 2005?
What is an application domain?
How is .NET Appdomain allocated in SQL SERVER 2005?
What is Syntax for creating a new assembly in SQL Server 2005?
Do Assemblies loaded in database need actual .NET DLL?
You have an assembly, which is dependent on other assemblies; will SQL
Server load the dependent assemblies?

Does SQL Server handle unmanaged resources?

Monday, January 10, 2011

21 top.net interview questions Part-2

21 top.net interview questions Part-2

This section is Part 2 and will cover top questions related to .net interview asked by the interviewer. So have a look on the following and do revise it when ever you go for the .net interview
Normally the .net interviewer starts with.....
How is stored procedure different from functions ?
What’s the difference between web services and remoting?
What’s the difference between WCF and Web services?
Which design patterns are you familiar with?
Can you explain singleton pattern?
What is MVC, MVP and MVVM pattern?
What are end point, contract, address, and bindings?
What are different phases in a software life cycle?
How did you do unit testing in your project?
How is ‘Server.Transfer’ different from ‘response. Redirect’ ?
Can you explain windows, forms and passport authentication?
Which are the various modes of storing ASP.NET session?
How can we do caching in ASP.NET?
What is ViewState?
What are indexes and what is the difference between clustered and
nonclustered?

What is WPF and silverlight?
What is LINQ and Entity framework?
What’s the difference between LINQ to SQL and Entity framework?
What is difference between Grid view, Data list, and repeater?
What are design patterns?
What is UML and which are the important diagrams?
Answer to the above given top .net interview questionsand clear the interview.

Saturday, January 8, 2011

22 top .net interview questions Part-1

22 top .net interview questions Part-1


This section is Part 1 and will cover top questions related to .net interview asked by the interviewer. So have a look on the following and do revise it when ever you go for the
.net interview
Normally the .net interviewer starts with.....

Can you explain architecture of your current project?

What role did you play in your project and company?
What’s your salary expectation?
Why do you want to leave your previous organization?
What is IL code, JIT, CLR, CTS, CLS and CAS?
What is a garbage collector?
What is GAC?
What are stack , heap , value , reference types , boxing and unboxing ?
What is try and catch block ?
What are different types of collections in .NET?
What are generics ?
Explain Abstraction, encapsulation, inheritance and polymorphism?
How is abstract class different from a interface ?
What are the types of polymorphism ?
How does delegate differ from a event?
What are different access modifiers?
Can you explain connection, command , datareader and dataset in ADO.NET ?
How does “Dataset” differ from a “Data Reader”?
How is ASP.NET page life cycle executed?
What are Httphandlers and HttpModules and difference between them?
What are different kind of validator controls in ASP.NET ?

Answer to the above given top .net interview questionsand clear the interview.

Friday, January 7, 2011

13 important SQL Server interview questions on notification, integration, reporting services

13 important SQL Server interview questions on notification, integration, reporting services


This section will cover the most asked SQL Server interview questions by the interviewer so have a look on the following and do revise it when ever you go for the SQL Server interview

Normally SQL Server interview starts with.....

What are notification services?
What are basic components of Notification services?
Can you explain architecture of Notification Services?
Which are the two XML files needed for notification services?
What are ADF and ACF XML files for?
What is Nscontrols command?
What are the situations you will use “Notification” Services?
What is Integration Services import / export wizard?
What are prime components in Integration Services?
How can we develop a DTS project in Integration Services?
Can you explain how can we make a simple report in reporting services?
How do I specify stored procedures in Reporting Services?
What is the architecture for “Reporting Services “?

So friends answering to above question on notification, integration, reporting services of SQL Server interview questions helped me to clear in front of the interviewer.

Thursday, January 6, 2011

22 important SQL Server interview questions on Transaction and Locks

22 important SQL Server interview questions on Transaction and Locks


This section will cover the most asked SQL Server interview questions by the interviewer so have a look on the following and do revise it when ever you go for the SQL Server interview

Normally SQL Server interview starts with.....


What is a “Database Transactions“?
What is ACID?
What is “Begin Trans”, “Commit Tran”, “Rollback Tran” and “SaveTran”?
What are “Checkpoint’s” in SQL Server?
What are “Implicit Transactions”?
Is it good to use “Implicit Transactions”?
What is Concurrency?
How can we solve concurrency problems?
What kind of problems occurs if we do not implement proper locking
strategy?

What are “Dirty reads”?
What are “Unrepeatable reads”?
What are “Phantom rows”?
What are “Lost Updates”?
What are different levels of granularity of locking resources?
What are different types of Locks in SQL Server?
What are different Isolation levels in SQL Server?
What are different types of Isolation levels in SQL Server?
If you are using COM+ what “Isolation” level is set by default?
What are “Lock” hints?
What is a “Deadlock”?
What are the steps you can take to avoid “Deadlocks”?
How can I know what locks are running on which resource?

So friends answering to above question on Transaction and Locks of SQL Server interview questions helped me to clear in front of the interviewer.

Wednesday, January 5, 2011

19 important SQL Server interview questionson Database Optimization

19 important SQL Server interview questionson Database Optimization

This section will cover the most asked SQL Server interview questions by the interviewer so have a look on the following and do revise it when ever you go for the SQL Server interview
Normally SQL Server interview starts with.....


What are indexes?
What are B-Trees?
I have a table which has lot of inserts, is it a good database design to
create indexes on that table?

What are “Table Scan’s” and “Index Scan’s”?
What are the two types of indexes and explain them in detail?
What is “FillFactor” concept in indexes?
What is the best value for “FillFactor”?
What are “Index statistics”?
How can we see statistics of an index?
How do you reorganize your index, once you find the problem?
What is Fragmentation?
How can we measure Fragmentation?
How can we remove the Fragmented spaces?
What are the criteria you will look in to while selecting an index?
What is “Index Tuning Wizard”?
How do you see the SQL plan in textual format?
What is Nested join, Hash join and Merge join in SQL Query plan?
What joins are good in what situations?
What is RAID and how does it work?

So friends answering to above question on Database Optimization of SQL Server interview questions helped me to clear in front of the interviewer.

Tuesday, January 4, 2011

19 important SQL Server interview questions on replication

19 importantSQL Server interview questions on replication


This section will cover the most asked SQL Server interview questions by the interviewer so have a look on the following and do revise it when ever you go for the SQL Server interview

Normally SQL Server interview starts with.....
What is the best way to update data between SQL Servers?
What are the scenarios you will need multiple databases with schema?
How will you plan your replication?
What are publisher, distributor and subscriber in “Replication”?
What is “Push” and “Pull” subscription?
Can a publication support push and pull at one time?
What are different models/types of replication?
What is Snapshot replication?
What are the advantages and disadvantages of using Snapshot replication?
What type of data will qualify for “Snapshot replication”?
What is the actual location where the distributor runs?
Can you explain in detail how exactly “Snapshot Replication” works?
What is merge replication?
How does merge replication works?
What are advantages and disadvantages of Merge replication?
What is conflict resolution in Merge replication?
What is a transactional replication?
Can you explain in detail how transactional replication works?
What are data type concerns during replications?

So friends answering to above question on replication of SQL Server interview questions helped me to clear in front of the interviewer.

Monday, January 3, 2011

23 important SQL Server interview questions on Database concepts

23 important SQL Server interview questions on Database concepts


This section will cover the most asked SQL Server interview questions by the interviewer so have a look on the following and do revise it when ever you go for the SQL Server interview
Normally SQL Server interview starts with.....

What is database or database management systems (DBMS)?
What is difference between DBMS and RDBMS?
What are CODD rules?
Is access database a RDBMS?
What is the main difference between ACCESS and SQL SERVER?
What is the difference between MSDE and SQL SERVER 2000?
What is SQL SERVER Express 2005 Edition?
What is SQL Server 2000 Workload Governor?
What is the difference between SQL SERVER 2000 and 2005?
What are E-R diagrams?
How many types of relationship exist in database designing?
What is normalization?
What are different type of normalization?
What is denormalization?
Can you explain Fourth Normal Form?
Can you explain Fifth Normal Form?
What is the difference between Fourth and Fifth normal form?
Have you heard about sixth normal form?
What is Extent and Page?
What are the different sections in Page?
What are page splits?
In which files does actually SQL Server store data?
Can we have a different collation for database and table?


So friends answering to above question on Database concepts of SQL Server interview questions helped me to clear in front of the interviewer.