I have tried many ways to update a table :UPDATE personnes T1 SET T1.nom_naiss=T1.nom FROM personnes T2, personnes T3
WHERE ....;UPDATE personnes T1 SET T1.nom_naiss=T1.nom FROM personnes T1, personnes T2, personnes T3
WHERE ..;In my case , where clause is : WHERE T1.id=T2.id_mere AND T2.id_pere=T3.id AND T1.nom != T3.nom;
Thanks. PC