Primary Key and Foreign Key in MySQL Explained with Examples | MySQL Tutorial

[@gauravpathak4479]

01:27 Primary key and foreign key constraints in relational databases
02:54 Creating a primary key in a database for unique identification
04:21 Foreign key creates linking between two tables
05:48 Foreign keys link the primary keys of two tables, enabling joint operations.
07:15 Creating a students table with primary and foreign keys
08:42 Creating a city table with id as primary key and city_id as foreign key
10:09 City ID 522 is located in city ID 609
11:29 Enforcing primary key and foreign key constraints is crucial in large-scale relational databases.

[@abdul_moiz_7]

Great explanation of this topic.

[@vinaymishra8533]

sir great work I had search more then 10 tutorials to find this concept but now it is clear

[@MuhammadAyaz_786]

what a great work sir

[@rksvlog2529]

Great....amazing technique

[@strangerealm796]

Sir table banai hai lekin bol rha hai referencing column city_id and referenced column cities (id)is incompatible.😢

[@rohitk472]

Best Explanation sir

[@manyadewangan6765]

I have a good doubt sir if we use primary key while creating columns then unique constraint ka koi use nhi hoga?

[@Bhumi_rai]

unique key mysql accept hi nhi karaga because 1 column pa 2 constraint nhi hote

[@hamzaarif6000]

Jab ap kisi column ko primary key set krtay ho to unique constraint lganay ka faida hi nahi q k primary key k column ki hr value unique e hoti hai. Primary key or Unique constraint mein difference ye hai k Primary key hum table k kisi aik column pr lga sktay hain jabkay unique constraint hum table k multiple columns pr lga sktay hain

[@hamzaarif6000]

​@@Bhumi_rai2 constraint ho sktay hain. Mainy try kiya tha or mere accept hogaye thy

[@nikhilmore3771]

PRIMARY KEY is parent
(confirm on other sources)

[@Akagarkar2024]

kodular ya thunkable per ek video upload kijiye sir please

[@strangerealm796]

Jinka error aa rha ho vo cities ki table me primary key (Id) rakhe phrr chal jayega.

[@puneetsharma8091]

Thanks

[@prasantaroutray2506]

bro are you from odisha?

[@vedsharma1933]

thanks

[@CodingMan-f1v]

Good explanation

[@theAdam586]

5. What is a foreign key? Write a query to implement the same in MySQL.
This is one of the prevalent MySQL queries interview questions for both beginner and experienced candidates. A foreign key is used to connect two tables. A FOREIGN KEY is a field (or assortment of it) in one table that alludes to the PRIMARY KEY in another table. The FOREIGN KEY requirement is utilised to forestall activities that would crush joins between tables.
To assign a foreign key, it is important to mention it while creating the table. It can be assigned by invoking the FOREIGN KEY query. Something like this:
FOREIGN KEY (Any_ID) REFERENCES Table_to_reference(Any_ID)

[@technicalrider6196]

Wrong teaching u have add primary key to city_id if ur refering city_id primary key to foreign key (cid)

[@RajeshKumar-jx9ql]

city_id kisi or table ki primary key hone wali h.....esa kyu hoga???? jbki kisi or table me to already primary ki hmne de rakhi h

[@coolanujkumar5]

missing index for constraint .... in the referenced table

[@divyanshsingh8807]

Solution h kya kuch

[@Ukmmtj1]

2:06 email bhi unique hi hota h🤔

[@MinabenPatel-u7v]

Ha hota hi haina 😮

[@bhaveshmorankar8579]

failed to add the foreign key dikha raha hai isko kaise solve kre?

[@lion7366]

Error Code: 1822. Failed to add the foreign key constraint. Missing index for constraint

[@khushiv2003]

Same problem

[@ruturajkadam5164]

​@@khushiv2003add constraint while adding foreign, you can give it any namr

[@vinaymishra8533]

sir pura syllabous nahi hua hai abhi

[@Roller_Roaster]

id mai 3 kyu show kr raha last mai?

[@vishnujatav6329]

important

[@shak1maangaming849]

failed to add misssing constraints error aa rha hai sir g??

[@Tadapatiatma]

Mila answe nhi mila to main bata sakta hun

[@divyanshsingh8807]

Koi batayega iska solution kya h

[@pulkitjadoun8596]

@@Tadapatiatma bata de bhai kese theek hoga

[@Tadapatiatma]

​@@pulkitjadoun8596 pehle apko 1st table Banna hai jismein apko primary key rakhna hai jo apka 2nd table ka foreign key hoaga means apko pehle 1st table ka primary key create karna ho ga tabhi to ap usko 2nd table mein foreign key aur reference de payenge

[@pulkitjadoun8596]

@@Tadapatiatma ok bro thanks

[@shelkeonka]

Sir 3 br try Kara laekin failed to add missing constraints error araha hai

[@Tadapatiatma]

Mila answer nhi mila to main bata sakta hun

[@gopalbarnwal7459]

@@Tadapatiatma bolo

[@rahuldatta1382]

@@gopalbarnwal7459 in the settings of cities, you have to select cid as a primary key

[@pulkitjadoun8596]

@@rahuldatta1382 kar liys fir bhi nahi ho raha

[@_.innovative_pixel]

8:00

[@harshadaborade5712]

Worst explanation

[@shubhamnimbalkar8659]

yedee chale mat kar aaise .....important portion tu bad mai sikha raha hai student ko ...primary key foreign key pahile sikhana tha....time wast

[@samiahirfanghouri1136]

Good explanation