-- /*check command */
-- The CHECK constraint is used to limit the value range that can be placed in a column.
-- If you define a CHECK constraint on a column it will allow only certain values for this column.
-- If you define a CHECK constraint on a table it can limit the values in certain columns based on values in other columns in the row.
-- The following CHECK constraint ensures that the age of a person must be 18, or older:
---------------------------------

create table student(id int,name varchar(255), address varchar(255), age int check (age>=23),salary int);
insert into student(id,name,address,age)values(1,"Harsh","Delhi",24);
insert into student(id,name,address,age)values(2,"Harsh","Delhi",24);
insert into student(id,name,address,age)values(3,"Harsh","Delhi",24);
insert into student(id,name,address,age)values(4,"Harsh","Delhi",24);
insert into student(id,name,address,age)values(5,"Harsh","Delhi",24);
insert into student(id,name,address,age)values(6,"Harsh","Delhi",24);
select * from student;