Constraints in database

Constraints in sql

RULES ABOUT THE COLUMNS IN TABLE
NOT NULL 	 # Ensures a column cannot have a NULL value
UNIQUE 		 # Ensures all values in a column are unique
PRIMARY KEY  # Identifies a record in a table, is NOT NULL & UNIQUE
FOREIGN KEY  # References a unique record from another table
CHECK		 # Ensures all column values satisfy a condition
DEFAULT		 # Set a default value for a column if none is entered
INDEX		 # Quick way of retrieving records from database

Constraints in database

<center> tag

Similar codes

0 vote328 views3 answers
Email validation pattern react
TypeScript
1 vote297 views1 answer
Ts version
TypeScript
1 vote317 views2 answers
Docker An attempt was made to access a socket in a way forbidden by its access permissions.
TypeScript
0 vote356 views1 answer
Subscripts list c#
TypeScript
-1 vote337 views1 answer
Typescript http get attach headers
TypeScript
0 vote353 views1 answer
How to call a function in a macro with variadic arguments c++
TypeScript
1 vote315 views1 answer
Selenium get all child elements python
TypeScript
0 vote338 views1 answer
Python append elements from one list to anoter
TypeScript
0 vote311 views1 answer
Fruits = ["apple", "banana", "cherry"] for x in fruits: print(x) if x == "banana": break Identify output ?
TypeScript
0 vote341 views1 answer
Get typescript props of component
TypeScript