Constraints Tutorial

List of Constraints in MySql :

1) NOT NULL

2) UNIQUE

3) DEFAULT

4) CHECK

5) FOREIGN KEY

6) PRIMARY KEY


CREATE TABLE table_name(

id INT NOT NULL UNIQUE,

name VARCHAR(50) NOT NULL,

age INT NOT NULL CHECK(age >= 18),

gender VARCHAR(10) NOT NULL,

phone VARCHAR(10) NOT NULL UNIQUE,

city VARCHAR(10) NOT NULL DEFAULT "Agra");

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