DDL (Data Definition Language) syntax example for a MySQL Database

my_db-ddl.sql

-- ddl my_db

-- create database my_db;
-- use my_db;
 
create table person(
    id int not null,
    name varchar(50),
    lastname varchar (40),
    age varchar (1),
    constraint primary key (id)
);
 
create table users(
    id int not null,
    id_person int not null,
    username varchar(50),
    constraint primary key (id),
    constraint fk_id_person foreign key (id_person) references person(id)
);