/Python/Foreign key and primary key difference

Foreign key and primary key difference

PrimaryKey:-

A primary key constrain is a column or group of columns that uniquely identifies every row in the table of the relational database management system. 
It cannot be a duplicate, meaning the same value should not appear more than once in the table.

Foreign key:-
A table can have more than one primary key. 
Primary key can be defined at the column or the table level.
If you create a composite primary key, it should be defined at the table level.
Foreign key is a column that creates a relationship between two tables. The purpose of the Foreign key is to maintain data integrity and allow navigation between two different instances of an entity. It acts as a cross-reference between two tables as it references the primary key of another table. 
Every relationship in the database should be supported by a foreign key.

Difference between primary key and foreign key

primary key and foreign key

-2

Similar codes

0 vote114 views1 answer
Installing intel python
Python
9 votes114 views4 answers
Change column order pandas
Python
34 votes134 views6 answers
Beautifulsoup python
Python
2 votes109 views1 answer
Distribution seaborn
Python
0 vote105 views1 answer
If statement collection python
Python
4 votes135 views3 answers
Flash messages django
Python Django
0 vote99 views1 answer
Python read in integers separated by spaces
Python
5 votes109 views2 answers
How to make a calcukatir un python
Python
0 vote112 views1 answer
|select name and description powershell
Python
0 vote102 views1 answer
Sowpods python
Python