diff --git a/db.h b/db.h
new file mode 100644
index 0000000..ef1c07e
--- /dev/null
+++ b/db.h
@@ -0,0 +1,32 @@
+#ifndef DB_H
+#define DB_H
+
+#include <string>
+#include <vector>
+#include "user.h"
+
+struct Student {
+    int id;
+    std::string nom;
+    int notes[3];
+};
+
+// --- Connexion et fermeture ---
+bool openDB(const std::string& filename);
+void closeDB();
+
+// --- Authentification ---
+int loginUser(const std::string& login, const std::string& password);
+
+// --- Étudiants ---
+std::vector<Student> getAllStudents();               // ADMIN/PROF
+Student getStudentByLogin(const std::string& login); // STUDENT
+
+// --- Notes ---
+bool updateNote(int studentId, int noteIndex, int newNote);
+
+// --- Export / Import ---
+bool exportData(const std::string& filename, const std::string& role, const std::string& login);
+bool importData(const std::string& filename, const std::string& role);
+
+#endif
\ No newline at end of file