Constraints

 CONSTRAINTS

Rules for data in the table

NOT NULL - defines that the column cannot have null value

UNIQUE - all values in that particular column are unique

DEFAULT - sets the  value of a column as a default value 

CHECK - can limit  the values allowed in a column




create database classss;

use classss;

CREATE TABLE users3(name VARCHAR(30) NOT NULL,mails VARCHAR(100) unique, followers INT DEFAULT 100 ,age INT, constraint age_check check(age>=13));

insert into users3 (name,mails,age) VALUES

("abhi","1253@mail",21),

("ash","2153@mail",23),

("bharath","1455@mail",31),

("vinay","495@mail",14);

SELECT * from users3;



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