47. UNIQUE KEY in SQL (Hindi)

[@yadneshkhode3091]

this is the best teaching channel on SQL in KZbin.... I'm lucky I found this..

[@geekyshows]

Thank You! Share with your friends and classmates

[@yadneshkhode3091]

Geeky Shows already did

[@sandeepthewanderer]

very well explained.....thank you

[@ALLCPL]

बहोत अच्छी वीडियो है। 👍👍👍

[@Ankurkumar14680]

Very informative, thanks for sharing

[@suvikash1033]

Thanks for teaching.

[@nitinmahajan8687]

Very nice explained 🙏🙏🙏🚩🚩🚩

[@technologybest3235]

All the Best teacher's

[@sabafathima8510]

By the value in unique key we can identify the whole record but if there are two null values in that column then how we can identify a particular record uniquely

[@geekyshows]

Even if there is only one NULL you can't identify that particular row becoz NULL contain some unknown value. I can understand your situation as well i m very impressed by your question. I cant believe that i forgot to discuss this part in this series. OK Let's talk about NULL what do you think about NULL i mean according to you what is NULL ? It seems you are taking NULL as string but NULL is something which doesn't really exists or we can't imagine what it could be or an unknown value. So Let's see this example there are two unknown person can u tell both these are same guy or different ? NO, You can't tell becoz you don't know them this is what NULL is. NULL (first unknown person) and NULL (2nd unknown person) it means NULL is not equal to NULL in SQL. I hope it is clear to you ?

[@sabafathima8510]

Geeky Shows k I know the functionality of NULL but as like primary key doesn't accept duplicate we have to give auto_constraint to it without which error appear similarly we should give auto_contraint to this also naaa ...... As the only difference between primary key n unique key is PK don't accept NULL values n UK accept it

[@geekyshows]

There is one more difference there can be only one PRIMARY KEY in a table while UNIQUE KEY may be more than one. Trust me you will understand the genuine use of UK and PK when you will do some real project for now i believe your concept has clear.

[@vickypatekar9532]

Too Good Teaching Sir!

[@SandeepKumar-so2st]

You are best

[@Adarsh-fj3kh]

Is it enough for data analyist

[@nishantsharma3673]

sir please explain how to import or export data from excel

[@atikapatel72]

Thank you so much sir

[@mudassirhashmiofficial]

good video but it should be short

[@amanbhargavaofficial]

Thank you 😊

[@shivanyasingh8878]

Nice sir!

[@rahulkarmore9739]

we also identify a record using primary key..so why we are use unique key

[@binodthakur6113]

suppose you have to fetch details by adhar card then adhar card number can me made unique - primary key is just auto-increment number.

[@rahulkarmore9739]

@@binodthakur6113 thanks for solved my confusion and also thanks for ur quick response😃

[@kiarakhan8805]

Where is stored procedures and triggers tutorials?

[@AmanGupta-ze9fc]

Can we add two null values in unique key field??

[@darknightcore9905]

Yes unique key will allow everything of its type but wont allow the duplicate but null is not equal to null so we can add multiple nulls

[@davidak115]

@@darknightcore9905 that's a lot of null xD

[@mandarsalunkhe09]

how to check which are the unique values in table ?

[@CodingHack]

agar unique key ko auto increment kr de toh kiya hoga explain

[@darknightcore9905]

Nothing.no errors as no duplicates

[@gauravthakare7221]

Different between primary Kay and unique kay

[@carrierbuilding4530]

*Sir is ka meaning kya ha?* Error SQL query: -- -- Indexes for dumped tables -- -- -- Indexes for table `ertable` -- ALTER TABLE `ertable` ADD PRIMARY KEY (`Sr`); MySQL said: Documentation #1068 - Multiple primary key defined

[@geekyshows]

Multiple primary key defined. One table can have only one Primary Key.

[@Sunshine-de1tb]

what is difference between unique key and primary key

[@debarghyachakraborty]

Primary key can be only one. Unique key can be multiple.

[@Sunshine-de1tb]

@@debarghyachakraborty thx

[@ektagarg7211]

Hello , I tried to use Alter command with UNIQUE but it is showing errror: alter table student add state varchar (10) UNIQUE KEY This command not working ..pls help

[@DeepakRaj1]

Why to use unique key when you can always use primary key?

[@RaghiPandit]

is unique key same as unique constraint?

[@debarghyachakraborty]

Yes, already mentioned in the video.

[@RaghiPandit]

@@debarghyachakraborty dude you are replying like a year later. I don't really care about that at this point lol

[@kiarakhan8805]

Views and permissions?

[@ManishKumar-yu8em]

please make a forigen key video

[@smartcode1325]

what is difference between primary key and unique

[@1k2a3r]

Difference between desc and select

[@Himanshu_Sharma..]

Desc gives you the meta data where as select helps in retrieving the information

[@sandeepsahu8743]

Sir....I think u r pursuing your IT degree from ignou ..So sir bca ya MCA kr rhe ho aap? Or sir web development k videos bnaye..How to become a good web developer?? Bahut help hogi sir

[@geekyshows]

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