alter table create constraint mysql code example
Example 1: mysql change foreign key
ALTER TABLE Orders
ADD FOREIGN KEY (PersonID) REFERENCES Persons(PersonID);
Example 2: my sql alter table
ALTER TABLE nom_table
MODIFY nom_colonne type_donnees
ALTER TABLE Orders
ADD FOREIGN KEY (PersonID) REFERENCES Persons(PersonID);
ALTER TABLE nom_table
MODIFY nom_colonne type_donnees