SQL Server Interview Questions and Answers | SQL Interview Questions

20 Plus SQL Server Interview Questions and Answers

Syllabus covered in this video :-
00:00 Introduction
01:22 Question 1 :- Explain normalization ?
04:45 Question 2 :- How to implement normalization ?
05:44 Question 3 :- What is denormalization ?
07:07 Question 4 :- Explain OLTP vs OLAP ?
10:40 Question 5 :- Explain 1st,2nd and 3rd Normal form ?
18:02 Question 6 :- Primary Key vs Unique key ?
20:02 Question 7 :- Differentiate between Char vs Varchar ?
21:32 Question 8 :- Differentiate between Char vs NChar ?
22:25 Question 9 :- Whats the size of Char vs NChar ?
23:32 Question 10 :- What is the use of Index ?
24:03 Question 11 :- How does it make search faster?
26:36 Question 12 :- What are the two types of Indexes ?
26:51 Question 13 :- Clustered vs Non-Clustered index
29:14 Question 14 :- Function vs Stored Procedures
33:27 Question 15 :- What are triggers and why do you need it ?
34:58 Question 16 :- What are types of triggers ?
36:57 Question 17 :- Differentiate between After trigger vs Instead Of ?
37:03 Question 18 :- What is need of Identity ?
38:10 Question 19 :- Explain transactions and how to implement it ?
42:55 Question 20 :- What are inner joins ?
45:00 Question 21 :- Explain Left join ?
46:25 Question 22 :- Explain Right join ?
46:40 Question 23 :- Explain Full outer joins ?
47:34 Question 24 :- Explain Cross joins ?

SQL Interview Questions & Answers - Part 2 :-
Question 25:-Why do we need UNION ?
Question 26:-Differentiate between Union vs Union All ?
Question 27:-can we have unequal columns in Union?
Question 28:-Can column have different data types in Union ?
Question 29:- Which Aggregate function have you used ?
Question 30:- When to use Group by ?
Question 31:- Can we select column which is not part of group by ?
Question 32:- What is having clause ?
Question 33:- Having clause vs Where clause
Question 34:- How can we sort records ?
Question 35:- Whats the default sort ?
Question 36:- How can we remove duplicates ?
Question 37:- Select the first top X records ?
Question 38:- How to handle NULLS ?
Question 39:- What is use of wild cards ?
Question 40:- What is the use of Alias ?
Question 41:- How to write a case statement ?
Question 42:- What is self reference tables ?
Question 43:- What is self join ?
Question 44:- Explain the between clause ?

SQL Interview Questions & Answers - Part 3 :-
Question 45:- Explain SubQuery?
Question 46:- Can inner Subquery return multiple results?
Question 47:- What is Co-related Query?
Question 48:- Differentiate between Joins and SubQuery?
Question 49:- Performance Joins vs SubQuery?

SQL Server Interview Questions & Answers - Part 4 :-
Question 50:- Find NTH Highest Salary in SQL.

SQL Server Interview Questions & Answers - Part 5
Question 51:- Select the top nth highest salary using correlated Queries?
Question 52:- Select top nth using using TSQL
Question 53:- Performance comparison of all the methods.

See our other Step by Step video series below :-

Music Copyright :-
Corporate Business by Infraction

If You want to contact the artist :-

#SQLQuestions #SQLInterviewQuestionsandAnswers #SQLServerQuestions

[VisionVibesNew]

I'm working since 3 years as a developer and i thought I'm a Superman in development. But going through this video i can say that i got very much & best technical knowledge... We implements thousands of things from theory but doesn't know their technical definitions and basic. Thank you Manish Sir for this best content.

I still remember my struggling days in Mumbai before 4 years ago and at that time too I was referring your videos on C#. At that time I even don't have a money to spend on the courses. But I took benifits from your YouTube channel. Today there are many channels on YT but at that time you was only one who were helping us... I must say that for all developers who come from middle & low class, you are super hero for all of us .... Thank You Sir!!

[rohit-gupta]

This video is so much better than all my college lectures combined. Thanks :)

[balajic]

great video to go through the Sql within 1 hour . Covered all the parts except functions . Thanks

[Victor-ynlv]

This video is amazing for SQL beginners to condense their SQL knowledge for interviews. Thank yo so much!

[inthumathy]

You are awesome. I have 6 years of experience in sql server but regarding normal forms and indexes I only knew the definition and never understood the actual concept. After watching this video I have clear understanding and I’ll never forget. You have awesome teaching skills. Thank you so much

[waqarkabir]

For quick review.
char takes 1 byte per character
N in char takes 2 bytes per character
Index = increase search performance, balance tree structure, nodes and leaf nodes
Index types = Clustered and Non-Clustered Indexes
Function = For computations, Only select is allowed, can be call by select and where and from stored procedures, should have 1 input with a return value. type can be scalar and table valued
Stored Procedures = CRUD ops, can not be called from select/where/other functions, can have single or multiple outputs, exec
Triggers = logic which can be execture after CRUD on any table
Trigger Types = after (do something on CRUD) and instead of (do some instead of CRUD or any query)
Identity = Auto incremented value of a column, seed
Transaction = treat series of activities as one logic unit
begin try
begin tran
insert into table1(column) values(value)
insert into table2(column) values(value)

commit tran
end try
begin catch
rollback
end catch

Inner join = Matching records from both tables

Left join = All records from table on left side of join and only matching records from right side table of join.

Right join = All records from table on right side of join and only matching records from left side table of join.

full outer join = all records from both tables are extracted and in case of non matching null is shown

cross join = cartesian product, every record of left table is multiplied with right table

[tiagosilva]

Very good job. Nice vid. Right to the point with clear and objective answers. Cheers from Portugal 🇵🇹

[erandafernando]

if this channel exisited when i did my bachelors, I would have gotten a first class lol.

[echonet]

so many questions for so many years have been answered here. Thanks so much!

[ayubmetah]

the instructor is very clear and audible.

[FusionTV]

One of the best video Frome 2 months of my YouTube search.. waiting for part 2..

[shivaaynamah]

Before watching this, I went through many videos and got a little information but this video gave a broader idea in very simple terms. It must be recommended to everyone who is going for an interview for database developer or business intelligence developer.

[divyasingh]

Very very well explained :)
Amazing content...best video I've ever seen on SQL....13 questions were asked by my interviewer from this video.

[abrahamvincent]

Good and clean explanation.with perfect examples.great job

[ebenss]

I love this vidoe thanks alot I'm presently taking classes on SQL server DBA

[santoshrout]

Got very much & best technical knowledge though I am into development for 2 Years. Techniques and way of presentation is superb.

[anilchaudhary]

Thank u so much shiv koirala sir for share the SQL interview questions series.👍

[tusharkantidas]

wonderfull. Completely clear explanations...LOVE IT.

[saurishroy]

Very nice video. 💯 To the point, no nonsense.

[mohsinpatel]

The basics are very smartly explained. Good knowledge. ❤