I am new to PhpMyAdmin. I will like to create a foreign key for my tables. In fact i have create tableI with this structures(A as int(11) autoincrement, B as varchar) TableII ( A_2 as int(11) auto increment, B_2 as varchar, A as int(11). I have declared A as an index in tableII, now when i go to relationship view to precise A as a foreign key i always have this error Erreur lors de la création de la clé étrangère sur ID_Ville (vérifiez le type des colonnes) Erreur ALTER TABLE tb_quartier ADD FOREIGN KEY ( ID_Ville ) REFERENCES ingenieris2.tb_ville ( ID_Ville ) ON DELETE RESTRICT ; Please Help thanks!