MCD — Modèle Conceptuel de Données

The MCD is the purely conceptual level (Merise methodology). It describes what the business needs to remember, independently of any database technology. No primary keys, no foreign keys, no SQL types — only business entities, their attributes, and the associations between them.

Entities

Entity	French name	Role
POLICE	Police d'assurance	The insurance contract between the company and the policyholder
GARANTIE	Garantie	A specific coverage included in the policy (what risk is covered and up to what amount)
PRIME	Prime	A payment instalment due on the policy

Diagram

Reading the cardinalities

Notation	Meaning
|| on POLICE side	One and only one POLICE per GARANTIE / PRIME
o{ on GARANTIE / PRIME side	Zero or more (a policy can have none yet, or many)

POLICE — couvrir — GARANTIE A policy covers one or more guarantees. A guarantee belongs to exactly one policy.

POLICE — appeler — PRIME A policy calls for one or more premium instalments. A premium belongs to exactly one policy.

Business rules captured

• statut ∈ (brouillon | actif | suspendu | résilié)
• date_effet < date_echeance (enforced at both domain and DB level)
• montant_assure > 0 — you cannot insure for zero
• franchise ≥ 0 — deductible can be zero (full coverage)
• montant (prime) > 0 — a premium must have a positive amount
• periodicite ∈ (mensuelle | trimestrielle | annuelle)
• date_paiement is optional — null means the premium has not been paid yet