corentin_wakdo/docs/merise/mld.md

Logical Data Model (MLD) — Wakdo

Merise phase : P1 - Conception, step 5 (after MCD, MCT, MLT) Version : v0.2 — prod-like, 19 tables Date : 2026-06-04 Branch : feat/p1-conception Status : prod-like — all D1-D8 + stock decisions applied (see docs/notes/revue-alignement-p1.md §7) Author : BYAN (methodology layer)

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1. Purpose of this document

The MLD transcribes the MCD into a formal relational schema: 1 entity -> 1 table, each association translated according to its cardinality, referential constraints materialised, indexes sized for frequent access patterns.

This is the step that transforms conceptual modelling into an implementable specification. The DDL SQL (db/migrations/0001_init_schema.sql) will be derived directly from this document at P2.

Sources:

• docs/merise/dictionary.md (v0.2 — types and constraints per attribute, source of truth)
• docs/merise/mcd.md (v0.2 — entities + cardinalities + deferred decisions)
• docs/notes/revue-alignement-p1.md §7 (decision table D1-D8 + stock)

Target platform:

• MariaDB 11.4 LTS (cf. docker-compose.yml service wakdo-db)
• Engine InnoDB (ACID, FK support, row-level locking, CHECK from 10.2.1)
• Charset utf8mb4, collation utf8mb4_unicode_ci

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2. Notation conventions

Relational notation

table_name (col1, col2, #col_fk, [col_nullable])

  PK  : col1
  UK  : col2
  FK  : col_fk -> other_table(id) ON DELETE <rule>
  IDX : (col_a, col_b)
  CHK : <expression>

Symbol	Meaning
col	NOT NULL column
[col]	Nullable column
#col	FK column

Notation follows Merise French usage (Nanci/Espinasse convention adapted for ASCII).

Type summary

All exact types are defined in dictionary.md section 2. Conventions retained:

• INT UNSIGNED AUTO_INCREMENT for all technical PKs
• INT UNSIGNED for all monetary amounts in cents (anti-FLOAT, see dictionary note 1)
• SMALLINT UNSIGNED for vat_rate per-mille values (55 or 100)
• ENUM(...) for stable business values (see dictionary note 2)
• DATETIME for timestamps (not TIMESTAMP, which implicitly converts to UTC in MariaDB)

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3. MCD -> MLD translation rules applied

3.1 Entity -> Table

Each MCD entity becomes one table. The conceptual identifier id becomes PK INT UNSIGNED AUTO_INCREMENT. Attributes retain their names and types.

3.2 (1,1) - (1,N) association -> simple FK

The entity on the (1,1) side carries the FK toward the (0,N) or (1,N) entity.

3.3 (0,N) - (0,N) or (1,N) - (1,N) association -> join table

The association becomes its own table with a composite PK of the two FKs. Applied to: product_ingredient, menu_slot_option, ingredient_allergen, role_visible_source, role_permission.

3.4 Associative entity with own attributes -> join table with columns

When an N-N association carries its own attributes, it becomes a table with those attributes in addition to the composite FK PK. Applied to product_ingredient.

3.5 Polymorphism -> 2 nullable FKs + discriminator + CHECK

order_item references either product or menu. Translated as 2 nullable FK columns + 1 discriminator ENUM + 1 CHECK constraint enforcing mutual exclusivity.

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4. Relational schema (19 tables)

Tables are ordered by dependency (no-FK tables first, then tables that depend on them).

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4.1 category

category (id, name, slug, [image_path], display_order, is_active, created_at, updated_at)

  PK  : id
  UK  : name
  UK  : slug

Column	Type	NULL	Notes
id	INT UNSIGNED AUTO_INCREMENT	NO	PK
name	VARCHAR(60)	NO	Unique display name (see dict 3.1)
slug	VARCHAR(60)	NO	URL slug, e.g. burgers
image_path	VARCHAR(255)	YES	Relative path from public root
display_order	SMALLINT UNSIGNED NOT NULL DEFAULT 0	NO	Kiosk display order
is_active	TINYINT(1) NOT NULL DEFAULT 1	NO	Soft deactivation
created_at	DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP	NO	Audit
updated_at	DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP	NO	Audit

No FK. Root table for the Catalogue sub-domain.

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4.2 product

product (id, #category_id, name, [description], price_cents, vat_rate,
         [image_path], is_available, display_order, created_at, updated_at)

  PK  : id
  FK  : category_id -> category(id) ON DELETE RESTRICT
  IDX : (category_id, is_available, display_order)
  CHK : price_cents > 0
  CHK : vat_rate IN (55, 100)

Column	Type	NULL	Notes
id	INT UNSIGNED AUTO_INCREMENT	NO	PK
category_id	INT UNSIGNED	NO	FK -> category
name	VARCHAR(120)	NO	Product label
description	TEXT	YES	Optional long description
price_cents	INT UNSIGNED	NO	A la carte price, incl. VAT, in cents
vat_rate	SMALLINT UNSIGNED	NO	Per-mille: 100 = 10%, 55 = 5.5%
image_path	VARCHAR(255)	YES	Relative path from public root
is_available	TINYINT(1) NOT NULL DEFAULT 1	NO	Manual availability toggle
display_order	SMALLINT UNSIGNED NOT NULL DEFAULT 0	NO	Within-category display order
created_at	DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP	NO	Audit
updated_at	DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP	NO	Audit

ON DELETE RESTRICT on category_id: a category with products cannot be deleted. Prevents orphaned products.

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4.3 menu

menu (id, #category_id, #burger_product_id, name, [description],
      price_normal_cents, price_maxi_cents, [image_path],
      is_available, display_order, created_at, updated_at)

  PK  : id
  FK  : category_id      -> category(id) ON DELETE RESTRICT
  FK  : burger_product_id -> product(id)  ON DELETE RESTRICT
  IDX : (category_id, is_available, display_order)
  CHK : price_normal_cents > 0
  CHK : price_maxi_cents > 0

Column	Type	NULL	Notes
id	INT UNSIGNED AUTO_INCREMENT	NO	PK
category_id	INT UNSIGNED	NO	FK -> category (typically the menus category)
burger_product_id	INT UNSIGNED	NO	FK -> product — the fixed burger that anchors this menu
name	VARCHAR(120)	NO	e.g. "Menu Le 280"
description	TEXT	YES	Optional
price_normal_cents	INT UNSIGNED	NO	Normal format price in cents
price_maxi_cents	INT UNSIGNED	NO	Maxi format price in cents (~+150 cents)
image_path	VARCHAR(255)	YES	Typically reuses the burger image
is_available	TINYINT(1) NOT NULL DEFAULT 1	NO	Availability toggle
display_order	SMALLINT UNSIGNED NOT NULL DEFAULT 0	NO	Display order
created_at	DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP	NO	Audit
updated_at	DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP	NO	Audit

ON DELETE RESTRICT on both FKs: prevents deletion of a category or burger product that is still referenced by a menu definition.

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4.4 menu_slot

menu_slot (id, #menu_id, name, slot_type, is_required, display_order)

  PK  : id
  FK  : menu_id -> menu(id) ON DELETE CASCADE
  IDX : (menu_id, display_order)

Column	Type	NULL	Notes
id	INT UNSIGNED AUTO_INCREMENT	NO	PK
menu_id	INT UNSIGNED	NO	FK -> menu
name	VARCHAR(80)	NO	e.g. "Drink", "Side", "Sauce"
slot_type	ENUM('drink','side','sauce','dessert','extra')	NO	Semantic role
is_required	TINYINT(1) NOT NULL DEFAULT 1	NO	Whether the customer must fill this slot
display_order	SMALLINT UNSIGNED NOT NULL DEFAULT 0	NO	Display order within menu builder

No audit fields: a slot is part of menu definition; created and updated together with the menu.

ON DELETE CASCADE on menu_id: if a menu is deleted, its slots are deleted with it.

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4.5 menu_slot_option

Pure join table. Composite PK.

menu_slot_option (#menu_slot_id, #product_id)

  PK  : (menu_slot_id, product_id)
  FK  : menu_slot_id -> menu_slot(id) ON DELETE CASCADE
  FK  : product_id   -> product(id)   ON DELETE RESTRICT

Column	Type	NULL	Notes
menu_slot_id	INT UNSIGNED	NO	FK -> menu_slot
product_id	INT UNSIGNED	NO	FK -> product

ON DELETE CASCADE on menu_slot_id: if a slot is deleted, its eligibility list goes with it. ON DELETE RESTRICT on product_id: a product listed as eligible in a slot cannot be deleted without first removing it from the slot options. Prevents silent breakage of menus.

No timestamps. Pure join table.

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4.6 ingredient

ingredient (id, name, unit, stock_quantity, pack_size, [pack_label],
            low_stock_threshold, is_active, created_at, updated_at)

  PK  : id
  UK  : name
  CHK : stock_quantity >= 0
  CHK : pack_size > 0
  CHK : low_stock_threshold >= 0

Column	Type	NULL	Notes
id	INT UNSIGNED AUTO_INCREMENT	NO	PK
name	VARCHAR(120)	NO	Unique name, e.g. "Sesame Bun"
unit	VARCHAR(40)	NO	Packaging unit label (free-form, not ENUM)
stock_quantity	INT NOT NULL DEFAULT 0	NO	Current stock. Signed INT to detect negative (alert)
pack_size	SMALLINT UNSIGNED NOT NULL DEFAULT 1	NO	Units per restocking pack
pack_label	VARCHAR(80)	YES	Human label of the pack
low_stock_threshold	SMALLINT UNSIGNED NOT NULL DEFAULT 0	NO	Alert threshold
is_active	TINYINT(1) NOT NULL DEFAULT 1	NO	Deactivate obsolete ingredients
created_at	DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP	NO	Audit
updated_at	DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP	NO	Audit

No FK. Root table for the Ingredients & Stock sub-domain.

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4.7 product_ingredient

Associative table carrying recipe and customisation metadata. Composite PK.

product_ingredient (#product_id, #ingredient_id, quantity_normal, quantity_maxi,
                    is_removable, is_addable, extra_price_cents)

  PK  : (product_id, ingredient_id)
  FK  : product_id    -> product(id)    ON DELETE CASCADE
  FK  : ingredient_id -> ingredient(id) ON DELETE RESTRICT
  CHK : quantity_normal > 0
  CHK : quantity_maxi >= quantity_normal
  CHK : extra_price_cents >= 0

Column	Type	NULL	Notes
product_id	INT UNSIGNED	NO	FK -> product
ingredient_id	INT UNSIGNED	NO	FK -> ingredient
quantity_normal	SMALLINT UNSIGNED NOT NULL DEFAULT 1	NO	Units consumed in Normal format
quantity_maxi	SMALLINT UNSIGNED NOT NULL DEFAULT 1	NO	Units consumed in Maxi format; equals quantity_normal for burger/sauce (format-invariant), higher for side/drink
is_removable	TINYINT(1) NOT NULL DEFAULT 1	NO	Customer may remove at no cost
is_addable	TINYINT(1) NOT NULL DEFAULT 0	NO	Customer may add an extra unit
extra_price_cents	INT UNSIGNED NOT NULL DEFAULT 0	NO	Surcharge if is_addable=1 and customer adds it

ON DELETE CASCADE on product_id: if a product is deleted, its recipe rows are deleted. ON DELETE RESTRICT on ingredient_id: cannot delete an ingredient still referenced in a recipe. Admin must remove the product-ingredient link first.

No timestamps. Join table with attributes.

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4.8 allergen

allergen (id, code, name, [description])

  PK  : id
  UK  : code

Column	Type	NULL	Notes
id	INT UNSIGNED AUTO_INCREMENT	NO	PK
code	VARCHAR(30)	NO	Machine code, e.g. gluten, milk
name	VARCHAR(80)	NO	Display name
description	TEXT	YES	Optional guidance

No FK. Reference table; 14 rows at seed (INCO Regulation (EU) 1169/2011). No updated_at: allergen catalogue is considered stable (additions require a migration, not a UI action).

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4.9 ingredient_allergen

Pure join table. Composite PK.

ingredient_allergen (#ingredient_id, #allergen_id)

  PK  : (ingredient_id, allergen_id)
  FK  : ingredient_id -> ingredient(id) ON DELETE CASCADE
  FK  : allergen_id   -> allergen(id)   ON DELETE RESTRICT

Column	Type	NULL	Notes
ingredient_id	INT UNSIGNED	NO	FK -> ingredient
allergen_id	INT UNSIGNED	NO	FK -> allergen

ON DELETE CASCADE on ingredient_id: if an ingredient is deleted, its allergen links go with it. ON DELETE RESTRICT on allergen_id: an allergen in the regulated catalogue cannot be deleted.

No timestamps. Pure join table.

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4.10 role

Placed before user because user depends on role.

role (id, code, label, [description], [default_route], [order_source],
      is_active, created_at, updated_at)

  PK  : id
  UK  : code

Column	Type	NULL	Notes
id	INT UNSIGNED AUTO_INCREMENT	NO	PK
code	VARCHAR(40)	NO	Machine code: admin, manager, kitchen, counter, drive
label	VARCHAR(80)	NO	Display name
description	TEXT	YES	Optional
default_route	VARCHAR(120)	YES	Landing screen, e.g. /admin/dashboard
order_source	ENUM('kiosk','counter','drive')	YES	Auto-tagged source when this role creates an order; NULL for admin/manager
is_active	TINYINT(1) NOT NULL DEFAULT 1	NO	Deactivation preserves history
created_at	DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP	NO	Audit
updated_at	DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP	NO	Audit

No FK. Root table for RBAC.

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4.11 user

user (id, email, password_hash, first_name, last_name, #role_id,
      is_active, [last_login_at], created_at, updated_at)

  PK  : id
  UK  : email
  FK  : role_id -> role(id) ON DELETE RESTRICT
  IDX : (is_active, role_id)

Column	Type	NULL	Notes
id	INT UNSIGNED AUTO_INCREMENT	NO	PK
email	VARCHAR(254)	NO	RFC 5321 max length
password_hash	VARCHAR(255)	NO	argon2id hash
first_name	VARCHAR(60)	NO
last_name	VARCHAR(60)	NO
role_id	INT UNSIGNED	NO	FK -> role
is_active	TINYINT(1) NOT NULL DEFAULT 1	NO	Deactivation without deletion
last_login_at	DATETIME	YES	Audit, dormant account detection
created_at	DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP	NO	Audit
updated_at	DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP	NO	Audit

ON DELETE RESTRICT on role_id: a role cannot be deleted while users hold it. Deactivate the role first (is_active = 0), then reassign users before deleting.

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4.12 role_visible_source

Pure join table. Composite PK.

role_visible_source (#role_id, source)

  PK  : (role_id, source)
  FK  : role_id -> role(id) ON DELETE CASCADE

Column	Type	NULL	Notes
role_id	INT UNSIGNED	NO	FK -> role
source	ENUM('kiosk','counter','drive')	NO	Order source visible on dashboard

ON DELETE CASCADE on role_id: if a role is deleted, its dashboard source filters go with it.

No timestamps. Pure join table.

Seed data:

• kitchen: kiosk, counter, drive
• counter: kiosk, counter
• drive: drive
• admin, manager: no rows (global view, no source filter)

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4.13 permission

permission (id, code, label, [description], created_at)

  PK  : id
  UK  : code

Column	Type	NULL	Notes
id	INT UNSIGNED AUTO_INCREMENT	NO	PK
code	VARCHAR(60)	NO	Format <resource>.<action>
label	VARCHAR(120)	NO	Display name
description	TEXT	YES	Optional
created_at	DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP	NO	Audit

No updated_at: permissions are declared in migration and not modified via UI. Catalogue is frozen at 23 codes (see dictionary section 3.17).

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4.14 role_permission

Pure join table. Composite PK.

role_permission (#role_id, #permission_id)

  PK  : (role_id, permission_id)
  FK  : role_id       -> role(id)       ON DELETE CASCADE
  FK  : permission_id -> permission(id) ON DELETE CASCADE
  IDX : permission_id

Column	Type	NULL	Notes
role_id	INT UNSIGNED	NO	FK -> role
permission_id	INT UNSIGNED	NO	FK -> permission

ON DELETE CASCADE on both FKs: deleting a role or a permission removes its mappings. The secondary index on permission_id supports the reverse query "which roles have this permission?" without scanning the full table.

No timestamps. Pure join table.

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4.15 customer_order

customer_order (id, order_number, source, service_mode, status,
                total_ht_cents, total_vat_cents, total_ttc_cents,
                [paid_at], [delivered_at], [cancelled_at],
                created_at, updated_at)

  PK  : id
  UK  : order_number
  IDX : (status, created_at)
  IDX : (source, created_at)
  IDX : created_at
  CHK : total_ht_cents >= 0
  CHK : total_vat_cents >= 0
  CHK : total_ttc_cents > 0
  CHK : total_ttc_cents = total_ht_cents + total_vat_cents
  CHK : source != 'drive' OR service_mode = 'drive'

Column	Type	NULL	Notes
id	INT UNSIGNED AUTO_INCREMENT	NO	PK
order_number	VARCHAR(20)	NO	Format K/C/D-YYYY-MM-DD-NNN by channel
source	ENUM('kiosk','counter','drive')	NO	Input channel
service_mode	ENUM('dine_in','takeaway','drive')	NO	Consumption mode (stats only, no fiscal role)
status	ENUM('pending_payment','paid','delivered','cancelled') NOT NULL DEFAULT 'pending_payment'	NO	4-state machine
total_ht_cents	INT UNSIGNED	NO	Ex-VAT total snapshot
total_vat_cents	INT UNSIGNED	NO	VAT amount snapshot
total_ttc_cents	INT UNSIGNED	NO	Incl.-VAT total; must equal HT + VAT
paid_at	DATETIME	YES	Timestamp of transition to paid
delivered_at	DATETIME	YES	Timestamp of transition to delivered
cancelled_at	DATETIME	YES	Timestamp of cancellation
created_at	DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP	NO	Used as service_day base
updated_at	DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP	NO	Audit

No FK toward user: staff attribution is not stored on the order. Operational accountability is covered by stock_movement.user_id for stock actions.

4-state machine: pending_payment -> paid -> delivered (+ cancelled). States preparing and ready are dropped (decision D4). KPI: delivered_at - paid_at (target SLA ~10 min).

service_day computation (used in stats queries — NOT a stored column):

CASE WHEN HOUR(created_at) < 10
     THEN DATE(created_at) - INTERVAL 1 DAY
     ELSE DATE(created_at)
END

Cutoff: 10:00. The generated-column formula with INTERVAL 4 HOUR 30 MINUTE from v0.1 was incorrect and is dropped (decision D6).

VAT calculation: totals on customer_order are the sum of line-level calculations. Line-level VAT: unit_price_cents_snapshot * quantity is the TTC amount per line; HT = ROUND(ttc_cents * 100 / (100 + vat_rate_per_cent)) where vat_rate_per_cent is vat_rate_snapshot / 10. Computed at application layer at cart validation.

source = 'drive' => service_mode = 'drive': the CHECK enforces this at DB level.

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4.16 order_item

order_item (id, #order_id, item_type, [#product_id], [#menu_id], format,
            label_snapshot, unit_price_cents_snapshot, vat_rate_snapshot,
            quantity, created_at)

  PK  : id
  FK  : order_id   -> customer_order(id) ON DELETE CASCADE
  FK  : product_id -> product(id)        ON DELETE RESTRICT
  FK  : menu_id    -> menu(id)           ON DELETE RESTRICT
  IDX : order_id
  CHK : unit_price_cents_snapshot > 0
  CHK : vat_rate_snapshot IN (55, 100)
  CHK : quantity > 0
  CHK : (item_type = 'product' AND product_id IS NOT NULL AND menu_id IS NULL)
        OR (item_type = 'menu' AND menu_id IS NOT NULL AND product_id IS NULL)

Column	Type	NULL	Notes
id	INT UNSIGNED AUTO_INCREMENT	NO	PK
order_id	INT UNSIGNED	NO	FK -> customer_order
item_type	ENUM('product','menu')	NO	Discriminator
product_id	INT UNSIGNED	YES	Non-null if item_type = 'product', NULL otherwise
menu_id	INT UNSIGNED	YES	Non-null if item_type = 'menu', NULL otherwise
format	ENUM('normal','maxi') NOT NULL DEFAULT 'normal'	NO	Menu format. For standalone products, value is normal
label_snapshot	VARCHAR(120)	NO	Label at time of order
unit_price_cents_snapshot	INT UNSIGNED	NO	Unit price incl. VAT at time of order
vat_rate_snapshot	SMALLINT UNSIGNED	NO	VAT rate per-mille at time of order
quantity	SMALLINT UNSIGNED NOT NULL DEFAULT 1	NO	Quantity (e.g. 3 drinks = 1 line, quantity=3)
created_at	DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP	NO	Audit

ON DELETE CASCADE on order_id: lines are deleted with the order. ON DELETE RESTRICT on product_id and menu_id: a product or menu referenced in an historical order line cannot be deleted. The snapshot makes the FK reference non-critical for display, but RESTRICT avoids silent orphaning of the relational structure.

Polymorphism exclusivity CHECK: MariaDB 10.2+ enforces this at INSERT/UPDATE time.

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4.17 order_item_selection

Customer's choice for one slot of a menu order line.

order_item_selection (id, #order_item_id, #menu_slot_id, #product_id, label_snapshot)

  PK  : id
  FK  : order_item_id -> order_item(id) ON DELETE CASCADE
  FK  : menu_slot_id  -> menu_slot(id)  ON DELETE RESTRICT
  FK  : product_id    -> product(id)    ON DELETE RESTRICT
  IDX : order_item_id

Column	Type	NULL	Notes
id	INT UNSIGNED AUTO_INCREMENT	NO	PK
order_item_id	INT UNSIGNED	NO	FK -> order_item (must be a menu-type line)
menu_slot_id	INT UNSIGNED	NO	FK -> menu_slot (which slot was filled)
product_id	INT UNSIGNED	NO	FK -> product (chosen by customer)
label_snapshot	VARCHAR(120)	NO	Product label at time of order

ON DELETE CASCADE on order_item_id: if the parent order line is deleted, its slot selections go with it. ON DELETE RESTRICT on menu_slot_id and product_id: historical slot choice records must not be silently broken by catalogue changes.

Note: the business constraint that order_item_id references a line with item_type='menu' is enforced at application layer (not in MariaDB without a trigger or deferred constraint).

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4.18 order_item_modifier

Ingredient-level modification applied by the customer to a product or the fixed burger of a menu.

order_item_modifier (id, #order_item_id, #ingredient_id, action, extra_price_cents)

  PK  : id
  FK  : order_item_id -> order_item(id)   ON DELETE CASCADE
  FK  : ingredient_id -> ingredient(id)   ON DELETE RESTRICT
  IDX : order_item_id
  CHK : extra_price_cents >= 0

Column	Type	NULL	Notes
id	INT UNSIGNED AUTO_INCREMENT	NO	PK
order_item_id	INT UNSIGNED	NO	FK -> order_item
ingredient_id	INT UNSIGNED	NO	FK -> ingredient
action	ENUM('remove','add')	NO	remove = free removal; add = extra unit
extra_price_cents	INT UNSIGNED NOT NULL DEFAULT 0	NO	Snapshot of surcharge at time of order (0 for removals)

ON DELETE CASCADE on order_item_id: if the order line is deleted, its modifiers go with it. ON DELETE RESTRICT on ingredient_id: an ingredient referenced in a historical modifier cannot be deleted.

Modifier attachment for menu lines: the modifiable product is the fixed burger, resolved via order_item.menu_id -> menu.burger_product_id. No additional FK column is needed on this table (see dictionary note 10).

---

4.19 stock_movement

Append-only audit log of all stock changes per ingredient.

stock_movement (id, #ingredient_id, movement_type, delta,
                [#order_id], [#user_id], [note], created_at)

  PK  : id
  FK  : ingredient_id -> ingredient(id)      ON DELETE RESTRICT
  FK  : order_id      -> customer_order(id)  ON DELETE SET NULL
  FK  : user_id       -> user(id)            ON DELETE SET NULL
  IDX : (ingredient_id, created_at)
  IDX : (movement_type, created_at)

Column	Type	NULL	Notes
id	INT UNSIGNED AUTO_INCREMENT	NO	PK
ingredient_id	INT UNSIGNED	NO	FK -> ingredient
movement_type	ENUM('sale','cancellation','restock','inventory_correction')	NO	Nature of movement
delta	INT	NO	Signed change: negative for consumption, positive for restock/cancellation/correction
order_id	INT UNSIGNED	YES	FK -> customer_order; non-null for sale and cancellation
user_id	INT UNSIGNED	YES	FK -> user; null for automated sale decrements
note	VARCHAR(255)	YES	Optional human note
created_at	DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP	NO	Immutable timestamp

ON DELETE RESTRICT on ingredient_id: an ingredient with a movement history cannot be deleted. Admin must archive the ingredient (is_active = 0) instead. ON DELETE SET NULL on order_id: if an order is purged from the system, its movement records remain with order_id = NULL. The audit log is preserved; only the order link is lost. ON DELETE SET NULL on user_id: if a user is deleted, movement records remain with user_id = NULL. Audit is preserved; individual attribution is lost.

Immutability rule: no UPDATE or DELETE at application layer. Corrections are new rows with movement_type = 'inventory_correction' and a signed delta.

No updated_at. Immutable append-only table.

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5. Referential integrity summary

FK column	References	ON DELETE	Rationale
product.category_id	category(id)	RESTRICT	No orphaned product
menu.category_id	category(id)	RESTRICT	Same
menu.burger_product_id	product(id)	RESTRICT	Menu definition requires its anchor burger
menu_slot.menu_id	menu(id)	CASCADE	Slots have no meaning without their menu
menu_slot_option.menu_slot_id	menu_slot(id)	CASCADE	Eligibility list disappears with the slot
menu_slot_option.product_id	product(id)	RESTRICT	Removing a product must not silently break menus
product_ingredient.product_id	product(id)	CASCADE	Recipe disappears with the product
product_ingredient.ingredient_id	ingredient(id)	RESTRICT	Cannot remove ingredient still in a recipe
ingredient_allergen.ingredient_id	ingredient(id)	CASCADE	Allergen links disappear with the ingredient
ingredient_allergen.allergen_id	allergen(id)	RESTRICT	Regulated allergen catalogue is immutable
user.role_id	role(id)	RESTRICT	A user cannot exist without a role
role_visible_source.role_id	role(id)	CASCADE	Dashboard filters disappear with the role
role_permission.role_id	role(id)	CASCADE	Permission mappings disappear with the role
role_permission.permission_id	permission(id)	CASCADE	Permission mappings disappear with the permission
order_item.order_id	customer_order(id)	CASCADE	Lines disappear with the order
order_item.product_id	product(id)	RESTRICT	Historical reference must not be silently orphaned
order_item.menu_id	menu(id)	RESTRICT	Same
order_item_selection.order_item_id	order_item(id)	CASCADE	Slot choices disappear with the line
order_item_selection.menu_slot_id	menu_slot(id)	RESTRICT	Historical slot record preserved
order_item_selection.product_id	product(id)	RESTRICT	Historical choice record preserved
order_item_modifier.order_item_id	order_item(id)	CASCADE	Modifiers disappear with the line
order_item_modifier.ingredient_id	ingredient(id)	RESTRICT	Historical modifier record preserved
stock_movement.ingredient_id	ingredient(id)	RESTRICT	Ingredient with history cannot be deleted
stock_movement.order_id	customer_order(id)	SET NULL	Audit preserved, order link lost
stock_movement.user_id	user(id)	SET NULL	Audit preserved, user attribution lost

Key used: CASCADE = child has no meaning without parent; RESTRICT = parent deletion blocked while children exist; SET NULL = child is preserved, only the link is severed.

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6. CHECK constraints summary

Table	CHECK expression	Purpose
product	price_cents > 0	Zero or negative price is a bug
product	vat_rate IN (55, 100)	Only two legal VAT rates for this model
menu	price_normal_cents > 0	Same as product
menu	price_maxi_cents > 0	Same
ingredient	stock_quantity >= 0	Negative stock is an alert, not a valid state
ingredient	pack_size > 0	Pack size of zero makes restock logic incoherent
ingredient	low_stock_threshold >= 0	Threshold cannot be negative
product_ingredient	quantity_normal > 0	Recipe quantity of zero is meaningless
product_ingredient	quantity_maxi >= quantity_normal	Maxi consumes at least as much as Normal (side/drink more, burger/sauce equal)
product_ingredient	extra_price_cents >= 0	No negative surcharge
customer_order	total_ht_cents >= 0	Zero is allowed (edge case during cart building)
customer_order	total_vat_cents >= 0	Same
customer_order	total_ttc_cents > 0	A validated order must have a positive total
customer_order	total_ttc_cents = total_ht_cents + total_vat_cents	Arithmetic invariant; defence-in-depth vs application bugs
customer_order	source != 'drive' OR service_mode = 'drive'	Cross-dimension constraint (dict. note 5)
order_item	unit_price_cents_snapshot > 0	Non-zero price at transaction time
order_item	vat_rate_snapshot IN (55, 100)	Snapshot must match allowed rates
order_item	quantity > 0	Non-zero quantity
order_item	(item_type='product' AND product_id IS NOT NULL AND menu_id IS NULL) OR (item_type='menu' AND menu_id IS NOT NULL AND product_id IS NULL)	Polymorphism: exactly one FK populated per discriminator value
order_item_modifier	extra_price_cents >= 0	Snapshot of surcharge; cannot be negative

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7. Recommended indexes (beyond PK / UK / FK auto-indexes)

MariaDB InnoDB creates an index automatically for each FK declaration (if no usable index exists). The following additional indexes target frequent query patterns identified in the MCT / MLT.

Table	Index columns	Query pattern
product	(category_id, is_available, display_order)	Kiosk catalogue load: filter by category + availability, sort by order
menu	(category_id, is_available, display_order)	Same pattern for menus
menu_slot	(menu_id, display_order)	Menu builder: load all slots of a menu in order
customer_order	(status, created_at)	Active orders queue: pending/paid orders sorted by time
customer_order	(source, created_at)	Per-channel analytics and order filtering
customer_order	created_at	Time-range aggregations (hourly stats, service_day)
order_item	order_id	Retrieve all lines of an order
order_item_selection	order_item_id	Retrieve slot choices for a menu line
order_item_modifier	order_item_id	Retrieve ingredient modifications for a line
stock_movement	(ingredient_id, created_at)	Per-ingredient stock history (dict. section 3.19)
stock_movement	(movement_type, created_at)	Stats: cancellations per week, restocks per month
role_permission	permission_id	Reverse query: "which roles have this permission?"
user	(is_active, role_id)	Login check + permission resolution

Indexes not added (intentional):

• customer_order.order_number: UK index is sufficient; no range query expected on this column.
• customer_order.service_mode: low cardinality (3 values); full scan on the status index with a service_mode filter is acceptable at expected volume.
• customer_order.paid_at: NULL for most in-flight rows; sparse index provides limited benefit.

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8. Cross-validation MLD <-> MCD

Verification that all 19 MCD entities map to a table, and that all tables trace to the MCD.

MCD entity	MLD table	Mapping type	Notes
category (C1)	category (4.1)	1:1 entity
product (C2)	product (4.2)	1:1 entity
menu (C3)	menu (4.3)	1:1 entity	New: burger_product_id, price_normal_cents, price_maxi_cents
menu_slot (C4)	menu_slot (4.4)	1:1 entity	New entity (v0.2)
menu_slot_option (C5)	menu_slot_option (4.5)	Join table (composite PK)	New entity (v0.2)
ingredient (C6)	ingredient (4.6)	1:1 entity	New entity (v0.2)
product_ingredient (C7)	product_ingredient (4.7)	Join table with attributes	New entity (v0.2)
allergen (C8)	allergen (4.8)	1:1 entity	New entity (v0.2)
ingredient_allergen (C9)	ingredient_allergen (4.9)	Join table (composite PK)	New entity (v0.2)
role (C10)	role (4.10)	1:1 entity	New: default_route, order_source
user (C11)	user (4.11)	1:1 entity	Columns renamed to English
role_visible_source (C12)	role_visible_source (4.12)	Join table (composite PK)	New entity (v0.2)
permission (C13)	permission (4.13)	1:1 entity
role_permission (C14)	role_permission (4.14)	Join table (composite PK)
customer_order (C15)	customer_order (4.15)	1:1 entity	Renamed from commande; 4-state machine; phase timestamps
order_item (C16)	order_item (4.16)	1:1 entity	New: format, vat_rate_snapshot; polymorphism CHECK
order_item_selection (C17)	order_item_selection (4.17)	1:1 entity	New entity (v0.2)
order_item_modifier (C18)	order_item_modifier (4.18)	1:1 entity	New entity (v0.2)
stock_movement (C19)	stock_movement (4.19)	1:1 entity	New entity (v0.2)

Result: 19/19 entities mapped. No entity without a table; no table outside the MCD.

Dropped from v0.1: commande_event (replaced by paid_at, delivered_at, cancelled_at phase timestamps on customer_order — decision 2.A); menu_produit fixed-composition model (replaced by menu_slot + menu_slot_option — decision D1).

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9. Volume estimation (6 months)

Table	Rows at 6 months	Avg row size	Est. size
category	~10	200 bytes	< 1 KB
product	~55	400 bytes	~22 KB
menu	~13	450 bytes	~6 KB
menu_slot	~40	150 bytes	~6 KB
menu_slot_option	~150	30 bytes	~5 KB
ingredient	~100	300 bytes	~30 KB
product_ingredient	~400	40 bytes	~16 KB
allergen	14	200 bytes	~3 KB
ingredient_allergen	~200	20 bytes	~4 KB
role	~5	200 bytes	~1 KB
user	~20	500 bytes	~10 KB
role_visible_source	~7	15 bytes	< 1 KB
permission	23	250 bytes	~6 KB
role_permission	~80	15 bytes	~2 KB
customer_order	~30k	300 bytes	~9 MB
order_item	~150k	250 bytes	~37 MB
order_item_selection	~300k	150 bytes	~45 MB
order_item_modifier	~150k	80 bytes	~12 MB
stock_movement	~500k	180 bytes	~90 MB

Estimated total: ~190 MB data + ~60-80 MB for indexes = ~250-270 MB over 6 months. Manageable on the MariaDB container (wakdo_db_data named volume in docker-compose.yml).

stock_movement is the highest-volume table (~5-15 rows per order across all ingredients). The (ingredient_id, created_at) index is the primary query path for per-ingredient history; it will carry meaningful write amplification at scale.

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10. Decisions deferred to DDL and P2

1. MariaDB generated column for service_day: a VIRTUAL GENERATED column is technically possible in MariaDB 5.7+ syntax. If stats queries prove burdensome without a materialised column, a STORED GENERATED column could be added as a migration. For this model, the applicative CASE expression is retained (simpler, avoids generated-column edge cases).
2. Partitioning: stock_movement could be partitioned by month if volume exceeds estimates. Not in scope for the initial DDL.
3. Triggers: stock decrement on paid transition and re-credit on cancelled (from paid) could be implemented as MariaDB triggers or as application-layer logic. To be decided at P2.
4. Collation: utf8mb4_unicode_ci retained (Unicode-compliant, case-insensitive). If strict French alphabetical sort is needed, utf8mb4_fr_0900_ai_ci is available in MySQL 8 but not MariaDB; unicode_ci is the portable choice.
5. Migration tooling: Phinx, Doctrine Migrations, or a plain PHP script. Decision at P2.
6. order_item_id constraint for selections: the business rule that order_item_selection.order_item_id must reference a line with item_type='menu' is enforced at application layer. A MariaDB trigger could reinforce this at DB level if needed.

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11. Next steps (DDL + Seed)

1. DDL (db/migrations/0001_init_schema.sql): transcribe this MLD into executable CREATE TABLE statements, in dependency order:

   • category -> product, ingredient, allergen, role
   • menu (depends on category, product)
   • menu_slot (depends on menu), menu_slot_option (depends on menu_slot, product)
   • product_ingredient (depends on product, ingredient)
   • ingredient_allergen (depends on ingredient, allergen)
   • user (depends on role), role_visible_source (depends on role)
   • permission, role_permission (depends on role, permission)
   • customer_order
   • order_item (depends on customer_order, product, menu)
   • order_item_selection (depends on order_item, menu_slot, product)
   • order_item_modifier (depends on order_item, ingredient)
   • stock_movement (depends on ingredient, customer_order, user)

2. Seed (db/seeds/0001_demo_data.sql):

   • 9 categories + 53 products + 13 menus from JSON sources (docs/merise/_sources/)
   • 13 menus with slots and slot options
   • 14 allergens (INCO EU 1169/2011)
   • Sample ingredient catalogue with recipes
   • 5 roles with role_permission matrix and role_visible_source data
   • 1 admin user
   • Sample orders for demo

3. Fallback JSON export (scripts/export-fallback.{sh|php}): extract seed data to src/public/borne/data/*.json for isolated kiosk mode (Bloc 1 without DB).

4. DDL validation tests: confirm CHECK constraints trigger as expected; confirm ON DELETE CASCADE / RESTRICT / SET NULL behaviours match specification.