Mariadb SQL FOREIGN KEY on CREATE TABLE code example
Example 1: mariadb add foreign key
alter table group_a
add constraint fk_b_in_a
foreign key(`b_id`)
references group_b(`b_id`)
on delete set null
on update set null;
Example 2: create table in mysql mariadb primary key foreign key
CREATE TABLE IF NOT EXISTS `scores` (
`ID` int(11) NOT NULL AUTO_INCREMENT,
UserId int(11) NOT NULL,
`NICKNAME` varchar(50) NOT NULL,
`HIGHSCORE` int(11) NOT NULL,
PRIMARY KEY (`ID`),
FOREIGN KEY (UserId) REFERENCES USER(Id)
);