1000 times better explanation than our college teachers.. 👍
@user-bk3zf5me7o
5 ай бұрын
Which university
@rajwindersinghlall1468
4 ай бұрын
True
@peterlor4126
9 күн бұрын
My professor doesn't even know what he's most of the time, thankfully we have the help we can get here. Thank you very much!
@ragapriyakarthikeyan3139
Жыл бұрын
The session is too engaging ,Sir. Got cleared with all the concepts🙂.Thankyou sir
@Hey_Haroon
Жыл бұрын
I m from non tech background and this topics comes in my Mba course and you explain it very smoothly. thank you !
@debasisnath9951
Жыл бұрын
from where are u pursuing mba? is it mba in IT?
@Hey_Haroon
Жыл бұрын
@@debasisnath9951 yes, From GL Bajaj institute greater Noida
@kawizekambowa3488
5 ай бұрын
Clear explanation indeed .
@nurlanacc1623
2 ай бұрын
@@Hey_Haroon Email in alone is superkeu? Because it has null row
@danielsims5771
Жыл бұрын
Oh my goodness. You explained the complex Lecture to a lay_man's view. I subscribed right away. Sending love from Zambia
@mutalekapambwe6882
11 ай бұрын
🇿🇲🇿🇲🇿🇲🇿🇲🇿🇲
@robertbehrens7026
Жыл бұрын
you explained it 10/10, thank you so much!
@BRIMACONTEH-d3v
Жыл бұрын
Such a great teacher with clean and clear explanation! thank you!
@aakankshakhawase1860
2 ай бұрын
Thank you for the explanation. Your explanation really helped in clearing the concepts regarding the keys.👍Great work!
@geetashah4430
8 күн бұрын
Good explanation 😊
@exploreyourself6776
Жыл бұрын
Precise And to the point.Well done 👍
@Torchbearer777
2 ай бұрын
Thank you for giving the knowledge about DBMS Keys ❤
@HetShah-ww8ph
Ай бұрын
One doubt : Super keys contain null values : {name,phone number} but if 1.{ john,null } and again in table we have 2.{john,null} than how we will identify the actual john than how it is valid…
@VigneshwaranS-n2i
4 ай бұрын
really! understood very clearly , mainly this session has been too engaging without lag.
@kawizekambowa3488
5 ай бұрын
It is not that difficult , it was just clarity i needed. Thank you
@m-47recordzz35
Жыл бұрын
Nicely explained , Thnxx alot 💙
@rayaneziadeh1879
Жыл бұрын
thank you for speaking clearly, finally found a video in which i can understand what its said
@KathirNatarajan-wk3nc
9 ай бұрын
Very very clear, really useful, wonderful explanation.great mentor u r sir, pls put more videos regarding dbms sir 🙏🙏🙏
@gauravsrivastava17
4 ай бұрын
clears all the concept about keys
@shrts-l8i
3 ай бұрын
1.75 X club
@MEHARAsad-n3e
21 күн бұрын
great ...explanation
@RenuSharma-iv7cs
6 ай бұрын
Very nicely explained
@funkiel-nowka
Жыл бұрын
@nesoacademy, are you sure that (Name, Phone) can be super key and candidate key? In "super key" part you've mentioned that you can not force an employee to have a phone number, so it can be null. What if we have in DB three employees named John without assigned phone number? 🤔🤔🤔
@baranhamoglu4072
Жыл бұрын
we need an answer to this, @funkiel-nowka if you found out can you explaine to me aswell ?
@baranhamoglu4072
Жыл бұрын
@Neso Academy
@haneenbaghdadi5966
11 ай бұрын
Even (Name, email) can't be a superkey coz what if email is Also null and the name might have repeated too...
@gokulnaathb2627
7 ай бұрын
You're right! I have the same doubt. Most probably, that part of the explanation is wrong.
@rocklee3254
3 ай бұрын
one thing i would like to add is that... (name + phone) cannot be a candidate key because they can have null values and the primary motive of candidate key is to uniquely identify a tuple. (name + phone) cannot be a primary key as well because primary key can't have null values.
@kabir73722
5 ай бұрын
Thanks very clear explanation
@Saha121-h6y
8 ай бұрын
Fantastic... Teaching..Great Sir Thank you sir
@jesusbrideindeed1657
9 ай бұрын
You are a great teacher
@sachinragu1742
Жыл бұрын
If one name is repeated twice and both the rows have null as their phone number then how will {name, phone} be a super key?
@Kanna12377
Жыл бұрын
{name, phone} is not a key because u can't identify a unique tuple by using this in that condition
@anusuyag5183
Жыл бұрын
@@Kanna12377for the super key u said like we can use name, phone as key right … that eg is coming for all candidate key primary key and alternative key.. then how come u r saying it’s not a keys
@Raven812
Жыл бұрын
It is candidate key
@ritasen225
Жыл бұрын
First you should make name and phone number as a key because it's not null but it's not not unique also
@queenkhan500
Жыл бұрын
Am also confused😢
@samuelayine418
5 ай бұрын
Great teacher !!!
@manasvikumarthakur5471
6 ай бұрын
Great Explaination Sir !!!!
@tuikasrivastava1763
2 ай бұрын
seriously better than my professor!!!
@atharva..deshmukh
3 күн бұрын
Excellent!!
@umaraju593
8 ай бұрын
very clear explanation. thank you
@abdullateefidris-jf3ub
11 ай бұрын
Well understood, Thanks❤
@regilearn2138
3 ай бұрын
Wow, appreciate you for this.
@modiallo968
7 ай бұрын
excellent work sir, thank you!
@Cobenis_Kar
Жыл бұрын
Beautifully explained, thank you!
@sanjeebamat4485
Жыл бұрын
Great lacture thank you for making such wonderful video .
@nitikaphogat8084
Ай бұрын
At 12:14 Wouldn't name ,email also be candidate key ...because name alone cannot be a key but when combined with phone number it become candidate key ....so I think name combined with email will also be candidate key ...... correct me if I am wrong
@ezanatadesa2485
29 күн бұрын
You're right, If PhoneNumber and Email are not unique across tuples then both {Name, PhoneNumber} and {Name, Email} can be candidate keys.
@JasGawera
9 күн бұрын
@@ezanatadesa2485 If Phone Number can be NULL, then (Name, Phone Number) cannot even be a candidate key can it? If John 101 and John 105 both have a NULL phone number then the key does not uniquely identify the tuple.
@monicabhattacharya9029
2 жыл бұрын
Thank you so much sir 😃😃👌
@dawaphunsumlodey153
Жыл бұрын
Simple and effective explanation. Thank you
@yusefiguess
3 ай бұрын
Thank you very much for the video. I have a question, why are we picking {Name, phone} and {email} as candidate keys instead of {Name, email} and {Phone}?
@giack6235
6 ай бұрын
Thank you for the very clear explanation. Just a question: at 11:50 you are considering among candidate keys also {Name, Phone} but according to definition, candidate key is a minimal set of attributes to be key. Since we have already considered {ID} and {SSN} as keys, minimal set of attributes to be key is 1, while in the case {Name, Phone} set of attribute is 2, which is greater. So why do we consider {Name, Phone} still as candidate key?
@sumanthkumar4035
6 ай бұрын
"minimal set of attributes" it implies that if you remove an attribute from it, it's no longer a key. minimal doesn't mean number of attributes, implies no extra attributes
@mohitzen
Жыл бұрын
Thank you sir 😊
@rivaldondezwenayo4028
Жыл бұрын
thank you i learnt alot from your work 😃😃😃😃😃😃
@shresth_bhakta
Жыл бұрын
Thanks NESO academy for this! Indeed and infromative video !
@tinkupavan565
7 ай бұрын
Super explanation 👌👌👌
@AhmadRazaNaveed
2 ай бұрын
Thanks for a lot
@HetShah-ww8ph
Ай бұрын
It is possible that both john have null phone numbers than how can we identify the actual john?????????? From the table ………
@userkanikanika
Ай бұрын
Simple It's ID ID is always Unique
@abizeta7507
11 ай бұрын
great teacher😊
@Bharathsuru
Жыл бұрын
Nice explanation 💥💥💯
@RishtonKiBaatein
Жыл бұрын
Thank you so much!
@adriand.2884
Жыл бұрын
Where is the tutorial of Normalization? I need it right now hehe, were done at keys in rdbms
@umabharathyts1998
2 ай бұрын
Thanks !
@statuslover4867
Жыл бұрын
Thank you sir for nice explanation ❤️
@sonuudarokar09
Жыл бұрын
You can add one thing here that is unique key allow only one null value....not more than one
@zeeleditz01
6 ай бұрын
Thankyou sir ✨
@A2Blearning1999
11 ай бұрын
Thank You
@hscodingdairies14
Жыл бұрын
Can someone please explain what is a unique key because it seemed same as alternate keys
@yoyo-hm2qo
6 ай бұрын
wonderful!!thanks,i understand it 100%😂
@talhashahid2176
4 күн бұрын
awesome
@ravindrathakur4563
Жыл бұрын
Thanks
@DaiMoscv
Жыл бұрын
(Name, email) what if the email is Null but the name alone cannot identify uniquely a tuple? In my opinion in this case it cannot be a superkey
@haneenbaghdadi5966
11 ай бұрын
Yess....even (Name, phone) can't be a super key...the phone no. Can also be null and the name can be repeated too...ig we hv to assign these attributes with certain keys separately....
@Amdebirhan_Abebe
Жыл бұрын
Thank you !
@utube_int2075
Жыл бұрын
So, super key is set of all possible combinations of attributes that can uniquely identify tuples. Is it right?
@Abhishek-jh9lz
10 ай бұрын
100/10 ❤
@kousik8042
Жыл бұрын
super key is like super set.but actually it is power set of keys
@sumanthkumar4035
6 ай бұрын
So, the unique key, must support null values apart from being unique ?
@anusuyag5183
Жыл бұрын
Unique key can b id or ssn right.. how come name, phone will be unique key
@enisozturk8075
Жыл бұрын
I have the same question how the phone number can be a unique key? There could be multiple nulls.
@tricks_without_treat
Жыл бұрын
Thanks bro
@Getagrip8
3 ай бұрын
In a candidate key what if one attribute values are not unique and other attributecan have a null value, How can we identify it...For example there are 3 john in the table and if two have no phone numbers then how can we identify the specific tuple
@nurlanacc1623
2 ай бұрын
Email in alone is superkeu? Because it has null row
@gokulnaathb2627
7 ай бұрын
Thank you
@mjordan1117
Жыл бұрын
why is salary on the table if you dont make use of it? Why is it not an alternate key?
@gottipadthasahithisahithig1137
4 ай бұрын
Sir could you post SQL tutorial
@shrutiagnihotri526
5 ай бұрын
If a column does not uniquely identify a tuple..it can't be a key...then how can u say email I'd can be a super key while it can contain null value
@GIGAlex6
5 ай бұрын
Composite key at 19:28
@aswin5226
11 ай бұрын
Is it possible for a unique and composite key to be something other than a candidate key?
@somendrasarkar7837
11 ай бұрын
Let's assume a airplane reservation system. What can be a primary key? Flight Number or Flight Number+Date
@Hahe2023
8 ай бұрын
I think both can act as a primary key but according to lecture " primary key should never and rarely be changed " 15:55 So there may be chance of date not mentioned (null) so flight number will definitely be a primary key.
@ishalkumar9037
Жыл бұрын
Which one was the foreign key ??? Dept. Code or any other ??
@hovering900
27 күн бұрын
Can only a null value be a candidate key?
@syedidrees7354
2 ай бұрын
how name and phone can be super key if there are 2 employees with same name and having null in their phone number field.
@SatyamMaurya..
6 ай бұрын
12:41 here , (salary and phone) too.
@samsonsumba7875
4 ай бұрын
Great
@Ganeshay-996
9 ай бұрын
Primary key --> PK PK is unique, NOT NULL, required , never duplicate and used for uniquely identify the data in table. every table have a max 1 PK. create table empinfo( id number primary key, ename varchar2(20), deptid number ); Unique key --> UK UK is unique, required, never duplicate and used for uniquely identify the data in table. table can have more than 1 unique key. UK allows null. every null is unique, we can not compare null to another null. thats why UK allows null, because it treats every null as unique. 10+null = null 10- null = null null is unknown and undefined, we do not know the value, so it always gives us null
@utsabbanerjee2770
9 ай бұрын
Lecturer key loves names like yusuf, alya, John , Robin etc.
@hosseinramezani5025
7 ай бұрын
l think Name and Phone togather cant be a super key, cause we can have two Johns that dont have phone numbers! please correct me if im wrong
@hewansolomon1973
6 ай бұрын
phone no is unique also it is can be null so it is super key i think
@gokulanvs
5 ай бұрын
In the super key what if two employees having same name both don't have phone number , how will you uniquely edit their data
@AlphaNOVA69
2 ай бұрын
Then it is not a super key, a super key should have attributes that are uniquely identifiable for each entry
@skyskitchen7872
7 ай бұрын
salary also can't be a superkey, right?
@C4_NETIC
6 ай бұрын
Yupp
@gokulnaathb2627
7 ай бұрын
How can {Name, Phone} uniquely identify a tuple? Phone is nullable, right?
@moatemsulongchar8418
6 ай бұрын
I think we can set it to NOT NULL
@steveboel12
7 ай бұрын
How can the set {Name, Phone} be a super key if multiple people can have the same name and not every person has a phone number?
@Debugger_97
5 ай бұрын
Super key is possible of all combinations even null attributes can be used
@Debugger_97
5 ай бұрын
Phone number alone and with others can be made super key but name won't !
@Debugger_97
5 ай бұрын
Ask ChatGpt after providing some attributes to it
@shivamtiwari9040
Жыл бұрын
at 19:19 name is not a unique key phone is a unique key and you are saying that set of name and phone is unique key, what if two employee of same name don't have phone number.
@kousik8042
Жыл бұрын
only phone number is also not a key. multiple employee might have no phone....2ndnot- employees with same name might also have no phone. so 'only name', 'only phone number', 'both name and phone number' are not keys...forget which type...those are not key first
@yoga_with_atharva
6 ай бұрын
why email is not unique key> as it is unique and null value
@poulomi1801
5 ай бұрын
some companies allow employees to have multiple email addresses, or they might have an email alias system where multiple employees share the same email domain. Additionally, allowing null values means that not all employees are required to have an email address, which further complicates setting it as a unique key.
@kavinarasan2619
Жыл бұрын
nandri thale
@varanaze.
Жыл бұрын
😂😂 Mass bro nee 😂
@obito3248
Жыл бұрын
bro in 12:42 {name,email } will come or not ?
@haneenbaghdadi5966
11 ай бұрын
No...becoz name attribute has already appeared ...in {Name, phone} so u can't have repeated attributes in candidate keys... same goes for email...see this part again 12:17 ...as u can see the email has also appeared once{Email} so u can't hv it again.
@hehehe9925
Жыл бұрын
can a candidate key have null values?pls anyone reply
@haneenbaghdadi5966
11 ай бұрын
Yess...Candidate key attribute can contain null values. Also know that it does not allow the same value in the attribute field.
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