What is primary key in simple words

Answer 1

You've many attributes of yours in Facebook like name, username, email, phone number, password, website, about, etc.

But you can only login with-
Either phone number or email
and
password

because these three are the primary keys to access rest of your database information.

Answer 2

primary key is the unique value that identify a record

Answer 3

primary is a unique value to identify something
par example table

Id Name Lastname
1 ccc ccc
2 ccc ccc

person can have same name or last name so you cant identify , while every person have different Id unique

Answer 4

a unique identifier

Answer 5

simple it is unique, And in my experience it almost come number,or auto number.

Answer 6

they function just as an id u need a person's number to call and not the name

Answer 7

It is a column used to join tables and garuntee the uniqueness of a row

Answer 8

It's the unique key value that is assigned to that table

Answer 9

primary key is assigned to the column which cannot have duplicate values and null values