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.

[@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

[@abdul_moiz_7]

Great explanation of this topic.

[@rksvlog2529]

Great....amazing technique

[@strangerealm796]

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

[@puneetsharma8091]

Thanks

[@strangerealm796]

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

[@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

[@rohitk472]

Best Explanation sir

[@nikhilmore3771]

PRIMARY KEY is parent (confirm on other sources)

[@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)

[@coolanujkumar5]

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

[@divyanshsingh8807]

Solution h kya kuch

[@Akagarkar2024]

kodular ya thunkable per ek video upload kijiye sir please

[@CodingMan-f1v]

Good explanation

[@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

[@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?

[@prasantaroutray2506]

bro are you from odisha?

[@vedsharma1933]

thanks

[@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

[@_.innovative_pixel]

8:00

[@vinaymishra8533]

sir pura syllabous nahi hua hai abhi

[@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

[@Roller_Roaster]

id mai 3 kyu show kr raha last mai?

[@harshadaborade5712]

Worst explanation

[@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

[@vishnujatav6329]

important

[@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