W3Schools SQL | #48 SQL CHECK CONSTRAINT

SQL CHECK Constraint

SQL CHECK Constraint

값의 범위를 제한하는 Constraint

SQL CHECK on CREATE TABLE

CREATE TABLE Persons (
    ID int NOT NULL.
    LastName varchar(255) NOT NULL,
    FirstName varchar(255),
    Age int, 
    CHECK (Age >= 18)
);

SQL CHECK on ALTER TABLE

ALTER TABLE Persons
ADD CHECK (Age >= 18);

DROP a CHECK Constraint

ALTER TABLE Persons
DROP CONSTRAINT CHK_PersonAge;