diff --git a/libfic/exercice.go b/libfic/exercice.go
index a428ca38..0a4b91fa 100644
--- a/libfic/exercice.go
+++ b/libfic/exercice.go
@@ -233,7 +233,7 @@ func (e Exercice) Delete() (int64, error) {
 
 // DeleteCascade the challenge from the database, including inner content but not player content.
 func (e Exercice) DeleteCascade() (int64, error) {
-	if _, err := DBExec("UPDATE exercices SET id_depend = NULL WHERE id_depend = ?", e.Id); err != nil {
+	if _, err := DBExec("UPDATE exercices SET depend = NULL WHERE depend = ?", e.Id); err != nil {
 		return 0, err
 	} else if _, err := DBExec("DELETE FROM exercice_files_okey_deps WHERE id_file IN (SELECT id_file FROM exercice_files WHERE id_exercice = ?)", e.Id); err != nil {
 		return 0, err
@@ -241,11 +241,13 @@ func (e Exercice) DeleteCascade() (int64, error) {
 		return 0, err
 	} else if _, err := DBExec("DELETE FROM exercice_files WHERE id_exercice = ?", e.Id); err != nil {
 		return 0, err
+	} else if _, err := DBExec("DELETE FROM exercice_hints_okey_deps WHERE id_hint IN (SELECT id_hint FROM exercice_hints WHERE id_exercice = ?)", e.Id); err != nil {
+		return 0, err
 	} else if _, err := DBExec("DELETE FROM exercice_hints WHERE id_exercice = ?", e.Id); err != nil {
 		return 0, err
 	} else if _, err := DBExec("DELETE FROM exercice_flags_deps WHERE id_flag IN (SELECT id_flag FROM exercice_flags WHERE id_exercice = ?)", e.Id); err != nil {
 		return 0, err
-	} else if _, err := DBExec("DELETE FROM exercice_flags_choices WHERE id_flag IN (SELECT id_flag FROM exercice_flags WHERE id_exercice = ?)", e.Id); err != nil {
+	} else if _, err := DBExec("DELETE FROM flag_choices WHERE id_flag IN (SELECT id_flag FROM exercice_flags WHERE id_exercice = ?)", e.Id); err != nil {
 		return 0, err
 	} else if _, err := DBExec("DELETE FROM exercice_flags WHERE id_exercice = ?", e.Id); err != nil {
 		return 0, err