diff --git a/tests/helpers/factories.ts b/tests/helpers/factories.ts
index d84291b..87df389 100644
--- a/tests/helpers/factories.ts
+++ b/tests/helpers/factories.ts
@@ -1,114 +1,115 @@
 /**
  * Test factory helpers.
- * These return plain data objects — NOT database-inserted records.
- * Safe to use whether or not a database is available.
+ *
+ * Two flavours:
+ *  1. Async DB-inserting factories (makePort, makeClient, makeBerth, makeYacht,
+ *     makeCompany, ...) — insert a row via the app's `db` handle and return the
+ *     inserted record. Use these from integration tests that need real FK /
+ *     unique-index enforcement. They require DATABASE_URL to be reachable.
+ *  2. Plain-data helpers (makeAuditMeta, makeCreateClientInput, makeCreate*)
+ *     — return in-memory objects suitable for unit tests with mocked `db`.
  */
 
+import { db } from '@/lib/db';
+import { ports, type NewPort, type Port } from '@/lib/db/schema/ports';
+import { clients, type NewClient, type Client } from '@/lib/db/schema/clients';
+import { berths, type NewBerth, type Berth } from '@/lib/db/schema/berths';
+import { yachts, yachtOwnershipHistory, type NewYacht, type Yacht } from '@/lib/db/schema/yachts';
+import { companies, type NewCompany, type Company } from '@/lib/db/schema/companies';
+
+// ─── Port ────────────────────────────────────────────────────────────────────
+
+export async function makePort(args?: { overrides?: Partial<NewPort> }): Promise<Port> {
+  const suffix = Math.random().toString(36).slice(2, 10);
+  const [port] = await db
+    .insert(ports)
+    .values({
+      name: args?.overrides?.name ?? `Test Port ${suffix}`,
+      slug: args?.overrides?.slug ?? `test-port-${suffix}`,
+      ...args?.overrides,
+    })
+    .returning();
+  return port!;
+}
+
 // ─── Client ──────────────────────────────────────────────────────────────────
 
-export interface ClientData {
-  id: string;
+export async function makeClient(args: {
   portId: string;
-  fullName: string;
-  companyName: string | null;
-  nationality: string | null;
-  isProxy: boolean;
-  source: string | null;
-  yachtLengthFt: string | null;
-  yachtLengthM: string | null;
-  archivedAt: Date | null;
-  createdAt: Date;
-  updatedAt: Date;
-}
-
-export function makeClient(overrides?: Partial<ClientData>): ClientData {
-  return {
-    id: crypto.randomUUID(),
-    portId: crypto.randomUUID(),
-    fullName: 'Test Client',
-    companyName: null,
-    nationality: null,
-    isProxy: false,
-    source: 'manual',
-    yachtLengthFt: null,
-    yachtLengthM: null,
-    archivedAt: null,
-    createdAt: new Date(),
-    updatedAt: new Date(),
-    ...overrides,
-  };
-}
-
-// ─── Interest ─────────────────────────────────────────────────────────────────
-
-export interface InterestData {
-  id: string;
-  portId: string;
-  clientId: string;
-  berthId: string | null;
-  pipelineStage: string;
-  leadCategory: string | null;
-  source: string | null;
-  eoiStatus: string | null;
-  contractStatus: string | null;
-  depositStatus: string | null;
-  notes: string | null;
-  archivedAt: Date | null;
-  createdAt: Date;
-  updatedAt: Date;
-}
-
-export function makeInterest(overrides?: Partial<InterestData>): InterestData {
-  return {
-    id: crypto.randomUUID(),
-    portId: crypto.randomUUID(),
-    clientId: crypto.randomUUID(),
-    berthId: null,
-    pipelineStage: 'open',
-    leadCategory: null,
-    source: 'manual',
-    eoiStatus: null,
-    contractStatus: null,
-    depositStatus: null,
-    notes: null,
-    archivedAt: null,
-    createdAt: new Date(),
-    updatedAt: new Date(),
-    ...overrides,
-  };
+  overrides?: Partial<NewClient>;
+}): Promise<Client> {
+  const [client] = await db
+    .insert(clients)
+    .values({
+      portId: args.portId,
+      fullName: args.overrides?.fullName ?? `Test Client ${Math.random().toString(36).slice(2, 8)}`,
+      ...args.overrides,
+    })
+    .returning();
+  return client!;
 }
 
 // ─── Berth ────────────────────────────────────────────────────────────────────
 
-export interface BerthData {
-  id: string;
+export async function makeBerth(args: {
   portId: string;
-  mooringNumber: string;
-  status: string;
-  area: string | null;
-  lengthM: string | null;
-  price: string | null;
-  tenureType: string | null;
-  archivedAt: Date | null;
-  createdAt: Date;
-  updatedAt: Date;
+  overrides?: Partial<NewBerth>;
+}): Promise<Berth> {
+  const [berth] = await db
+    .insert(berths)
+    .values({
+      portId: args.portId,
+      mooringNumber: args.overrides?.mooringNumber ?? `B-${Math.random().toString(36).slice(2, 8)}`,
+      ...args.overrides,
+    })
+    .returning();
+  return berth!;
 }
 
-export function makeBerth(overrides?: Partial<BerthData>): BerthData {
-  return {
-    id: crypto.randomUUID(),
-    portId: crypto.randomUUID(),
-    mooringNumber: `B-${Math.floor(Math.random() * 999) + 1}`,
-    status: 'available',
-    area: null,
-    lengthM: '12',
-    price: '50000',
-    tenureType: 'freehold',
-    archivedAt: null,
-    createdAt: new Date(),
-    updatedAt: new Date(),
-    ...overrides,
-  };
+// ─── Yacht ───────────────────────────────────────────────────────────────────
+
+export async function makeYacht(args: {
+  portId: string;
+  ownerType: 'client' | 'company';
+  ownerId: string;
+  overrides?: Partial<NewYacht>;
+}): Promise<Yacht> {
+  const [yacht] = await db
+    .insert(yachts)
+    .values({
+      portId: args.portId,
+      name: args.overrides?.name ?? `Yacht ${Math.random().toString(36).slice(2, 8)}`,
+      currentOwnerType: args.ownerType,
+      currentOwnerId: args.ownerId,
+      ...args.overrides,
+    })
+    .returning();
+  await db.insert(yachtOwnershipHistory).values({
+    yachtId: yacht!.id,
+    ownerType: args.ownerType,
+    ownerId: args.ownerId,
+    startDate: new Date(),
+    endDate: null,
+    createdBy: 'test',
+  });
+  return yacht!;
+}
+
+// ─── Company ─────────────────────────────────────────────────────────────────
+
+export async function makeCompany(args: {
+  portId: string;
+  overrides?: Partial<NewCompany>;
+}): Promise<Company> {
+  const [company] = await db
+    .insert(companies)
+    .values({
+      portId: args.portId,
+      name: args.overrides?.name ?? `Company ${Math.random().toString(36).slice(2, 8)}`,
+      ...args.overrides,
+    })
+    .returning();
+  return company!;
 }
 
 // ─── Webhook ──────────────────────────────────────────────────────────────────
@@ -169,14 +170,50 @@ import type { RolePermissions } from '@/lib/db/schema/users';
 export function makeFullPermissions(): RolePermissions {
   return {
     clients: { view: true, create: true, edit: true, delete: true, merge: true, export: true },
-    interests: { view: true, create: true, edit: true, delete: true, change_stage: true, generate_eoi: true, export: true },
+    interests: {
+      view: true,
+      create: true,
+      edit: true,
+      delete: true,
+      change_stage: true,
+      generate_eoi: true,
+      export: true,
+    },
     berths: { view: true, edit: true, import: true, manage_waiting_list: true },
-    documents: { view: true, create: true, send_for_signing: true, upload_signed: true, delete: true },
-    expenses: { view: true, create: true, edit: true, delete: true, export: true, scan_receipt: true },
-    invoices: { view: true, create: true, edit: true, delete: true, send: true, record_payment: true, export: true },
+    documents: {
+      view: true,
+      create: true,
+      send_for_signing: true,
+      upload_signed: true,
+      delete: true,
+    },
+    expenses: {
+      view: true,
+      create: true,
+      edit: true,
+      delete: true,
+      export: true,
+      scan_receipt: true,
+    },
+    invoices: {
+      view: true,
+      create: true,
+      edit: true,
+      delete: true,
+      send: true,
+      record_payment: true,
+      export: true,
+    },
     files: { view: true, upload: true, delete: true, manage_folders: true },
     email: { view: true, send: true, configure_account: true },
-    reminders: { view_own: true, view_all: true, create: true, edit_own: true, edit_all: true, assign_others: true },
+    reminders: {
+      view_own: true,
+      view_all: true,
+      create: true,
+      edit_own: true,
+      edit_all: true,
+      assign_others: true,
+    },
     calendar: { connect: true, view_events: true },
     reports: { view_dashboard: true, view_analytics: true, export: true },
     document_templates: { view: true, generate: true, manage: true },
@@ -198,14 +235,50 @@ export function makeFullPermissions(): RolePermissions {
 export function makeViewerPermissions(): RolePermissions {
   return {
     clients: { view: true, create: false, edit: false, delete: false, merge: false, export: false },
-    interests: { view: true, create: false, edit: false, delete: false, change_stage: false, generate_eoi: false, export: false },
+    interests: {
+      view: true,
+      create: false,
+      edit: false,
+      delete: false,
+      change_stage: false,
+      generate_eoi: false,
+      export: false,
+    },
     berths: { view: true, edit: false, import: false, manage_waiting_list: false },
-    documents: { view: true, create: false, send_for_signing: false, upload_signed: false, delete: false },
-    expenses: { view: true, create: false, edit: false, delete: false, export: false, scan_receipt: false },
-    invoices: { view: true, create: false, edit: false, delete: false, send: false, record_payment: false, export: false },
+    documents: {
+      view: true,
+      create: false,
+      send_for_signing: false,
+      upload_signed: false,
+      delete: false,
+    },
+    expenses: {
+      view: true,
+      create: false,
+      edit: false,
+      delete: false,
+      export: false,
+      scan_receipt: false,
+    },
+    invoices: {
+      view: true,
+      create: false,
+      edit: false,
+      delete: false,
+      send: false,
+      record_payment: false,
+      export: false,
+    },
     files: { view: true, upload: false, delete: false, manage_folders: false },
     email: { view: true, send: false, configure_account: false },
-    reminders: { view_own: true, view_all: false, create: false, edit_own: false, edit_all: false, assign_others: false },
+    reminders: {
+      view_own: true,
+      view_all: false,
+      create: false,
+      edit_own: false,
+      edit_all: false,
+      assign_others: false,
+    },
     calendar: { connect: false, view_events: true },
     reports: { view_dashboard: true, view_analytics: false, export: false },
     document_templates: { view: true, generate: false, manage: false },
@@ -227,14 +300,50 @@ export function makeViewerPermissions(): RolePermissions {
 export function makeSalesAgentPermissions(): RolePermissions {
   return {
     clients: { view: true, create: true, edit: true, delete: false, merge: false, export: false },
-    interests: { view: true, create: true, edit: true, delete: false, change_stage: true, generate_eoi: true, export: false },
+    interests: {
+      view: true,
+      create: true,
+      edit: true,
+      delete: false,
+      change_stage: true,
+      generate_eoi: true,
+      export: false,
+    },
     berths: { view: true, edit: false, import: false, manage_waiting_list: false },
-    documents: { view: true, create: true, send_for_signing: true, upload_signed: true, delete: false },
-    expenses: { view: true, create: true, edit: true, delete: false, export: false, scan_receipt: true },
-    invoices: { view: true, create: false, edit: false, delete: false, send: false, record_payment: false, export: false },
+    documents: {
+      view: true,
+      create: true,
+      send_for_signing: true,
+      upload_signed: true,
+      delete: false,
+    },
+    expenses: {
+      view: true,
+      create: true,
+      edit: true,
+      delete: false,
+      export: false,
+      scan_receipt: true,
+    },
+    invoices: {
+      view: true,
+      create: false,
+      edit: false,
+      delete: false,
+      send: false,
+      record_payment: false,
+      export: false,
+    },
     files: { view: true, upload: true, delete: false, manage_folders: false },
     email: { view: true, send: true, configure_account: false },
-    reminders: { view_own: true, view_all: false, create: true, edit_own: true, edit_all: false, assign_others: false },
+    reminders: {
+      view_own: true,
+      view_all: false,
+      create: true,
+      edit_own: true,
+      edit_all: false,
+      assign_others: false,
+    },
     calendar: { connect: true, view_events: true },
     reports: { view_dashboard: true, view_analytics: false, export: false },
     document_templates: { view: true, generate: true, manage: false },
@@ -256,14 +365,50 @@ export function makeSalesAgentPermissions(): RolePermissions {
 export function makeSalesManagerPermissions(): RolePermissions {
   return {
     clients: { view: true, create: true, edit: true, delete: true, merge: true, export: true },
-    interests: { view: true, create: true, edit: true, delete: true, change_stage: true, generate_eoi: true, export: true },
+    interests: {
+      view: true,
+      create: true,
+      edit: true,
+      delete: true,
+      change_stage: true,
+      generate_eoi: true,
+      export: true,
+    },
     berths: { view: true, edit: true, import: false, manage_waiting_list: true },
-    documents: { view: true, create: true, send_for_signing: true, upload_signed: true, delete: true },
-    expenses: { view: true, create: true, edit: true, delete: true, export: true, scan_receipt: true },
-    invoices: { view: true, create: true, edit: true, delete: false, send: true, record_payment: true, export: true },
+    documents: {
+      view: true,
+      create: true,
+      send_for_signing: true,
+      upload_signed: true,
+      delete: true,
+    },
+    expenses: {
+      view: true,
+      create: true,
+      edit: true,
+      delete: true,
+      export: true,
+      scan_receipt: true,
+    },
+    invoices: {
+      view: true,
+      create: true,
+      edit: true,
+      delete: false,
+      send: true,
+      record_payment: true,
+      export: true,
+    },
     files: { view: true, upload: true, delete: true, manage_folders: true },
     email: { view: true, send: true, configure_account: false },
-    reminders: { view_own: true, view_all: true, create: true, edit_own: true, edit_all: true, assign_others: true },
+    reminders: {
+      view_own: true,
+      view_all: true,
+      create: true,
+      edit_own: true,
+      edit_all: true,
+      assign_others: true,
+    },
     calendar: { connect: true, view_events: true },
     reports: { view_dashboard: true, view_analytics: true, export: true },
     document_templates: { view: true, generate: true, manage: false },
@@ -306,7 +451,15 @@ export function makeCreateClientInput(overrides?: { fullName?: string; portId?:
 /** Returns a minimal valid CreateInterestInput object. */
 export function makeCreateInterestInput(overrides?: {
   clientId?: string;
-  pipelineStage?: 'open' | 'details_sent' | 'in_communication' | 'visited' | 'signed_eoi_nda' | 'deposit_10pct' | 'contract' | 'completed';
+  pipelineStage?:
+    | 'open'
+    | 'details_sent'
+    | 'in_communication'
+    | 'visited'
+    | 'signed_eoi_nda'
+    | 'deposit_10pct'
+    | 'contract'
+    | 'completed';
 }) {
   return {
     clientId: overrides?.clientId ?? crypto.randomUUID(),
diff --git a/tests/integration/schema-constraints.test.ts b/tests/integration/schema-constraints.test.ts
new file mode 100644
index 0000000..72f0750
--- /dev/null
+++ b/tests/integration/schema-constraints.test.ts
@@ -0,0 +1,169 @@
+/**
+ * Schema constraint integration tests.
+ *
+ * Verifies DB-level enforcement of:
+ *  - Partial unique index idx_yoh_active (one active ownership row per yacht)
+ *  - Partial unique index idx_br_active (one active reservation per berth)
+ *  - Non-active reservations on the same berth are permitted
+ *  - Case-insensitive company name uniqueness within a port
+ *  - Same company name allowed across different ports
+ */
+import { describe, it, expect, beforeAll } from 'vitest';
+
+import { db } from '@/lib/db';
+import { yachtOwnershipHistory } from '@/lib/db/schema/yachts';
+import { berthReservations } from '@/lib/db/schema/reservations';
+import { companies } from '@/lib/db/schema/companies';
+import { makeBerth, makeClient, makeCompany, makePort, makeYacht } from '../helpers/factories';
+
+// ─── DB availability ─────────────────────────────────────────────────────────
+
+let dbAvailable = false;
+
+beforeAll(async () => {
+  try {
+    await db.execute(`SELECT 1`);
+    dbAvailable = true;
+  } catch (err) {
+    console.warn(
+      '[schema-constraints] DATABASE_URL not reachable — skipping integration tests',
+      err,
+    );
+  }
+});
+
+function itDb(name: string, fn: () => Promise<void>) {
+  it(name, async () => {
+    if (!dbAvailable) return;
+    await fn();
+  });
+}
+
+// ─── Tests ───────────────────────────────────────────────────────────────────
+
+describe('schema constraints', () => {
+  itDb(
+    'rejects a second active ownership row per yacht (partial unique idx_yoh_active)',
+    async () => {
+      const port = await makePort();
+      const clientA = await makeClient({ portId: port.id });
+      const clientB = await makeClient({ portId: port.id });
+      const yacht = await makeYacht({
+        portId: port.id,
+        ownerType: 'client',
+        ownerId: clientA.id,
+      });
+      // makeYacht already inserted one active (end_date IS NULL) ownership row.
+
+      await expect(
+        db.insert(yachtOwnershipHistory).values({
+          yachtId: yacht.id,
+          ownerType: 'client',
+          ownerId: clientB.id,
+          startDate: new Date(),
+          endDate: null, // another open row — should violate partial unique
+          createdBy: 'test',
+        }),
+      ).rejects.toThrow(/duplicate key|unique/i);
+    },
+  );
+
+  itDb('rejects a second active reservation per berth (partial unique idx_br_active)', async () => {
+    const port = await makePort();
+    const clientA = await makeClient({ portId: port.id });
+    const clientB = await makeClient({ portId: port.id });
+    const yachtA = await makeYacht({
+      portId: port.id,
+      ownerType: 'client',
+      ownerId: clientA.id,
+    });
+    const yachtB = await makeYacht({
+      portId: port.id,
+      ownerType: 'client',
+      ownerId: clientB.id,
+    });
+    const berth = await makeBerth({ portId: port.id });
+
+    await db.insert(berthReservations).values({
+      berthId: berth.id,
+      portId: port.id,
+      clientId: clientA.id,
+      yachtId: yachtA.id,
+      status: 'active',
+      startDate: new Date(),
+      createdBy: 'test',
+    });
+
+    await expect(
+      db.insert(berthReservations).values({
+        berthId: berth.id,
+        portId: port.id,
+        clientId: clientB.id,
+        yachtId: yachtB.id,
+        status: 'active',
+        startDate: new Date(),
+        createdBy: 'test',
+      }),
+    ).rejects.toThrow(/duplicate key|unique/i);
+  });
+
+  itDb(
+    'allows multiple non-active reservations on the same berth (partial index ignores non-active)',
+    async () => {
+      const port = await makePort();
+      const clientA = await makeClient({ portId: port.id });
+      const yachtA = await makeYacht({
+        portId: port.id,
+        ownerType: 'client',
+        ownerId: clientA.id,
+      });
+      const berth = await makeBerth({ portId: port.id });
+
+      // Two ended reservations on same berth — both should succeed
+      // (partial index only constrains status='active').
+      await expect(
+        db.insert(berthReservations).values([
+          {
+            berthId: berth.id,
+            portId: port.id,
+            clientId: clientA.id,
+            yachtId: yachtA.id,
+            status: 'ended',
+            startDate: new Date('2024-01-01'),
+            endDate: new Date('2024-06-30'),
+            createdBy: 'test',
+          },
+          {
+            berthId: berth.id,
+            portId: port.id,
+            clientId: clientA.id,
+            yachtId: yachtA.id,
+            status: 'ended',
+            startDate: new Date('2024-07-01'),
+            endDate: new Date('2024-12-31'),
+            createdBy: 'test',
+          },
+        ]),
+      ).resolves.toBeDefined();
+    },
+  );
+
+  itDb('enforces case-insensitive company name uniqueness per port', async () => {
+    const port = await makePort();
+    await makeCompany({ portId: port.id, overrides: { name: 'Aegean Holdings' } });
+
+    await expect(
+      db.insert(companies).values({ portId: port.id, name: 'AEGEAN HOLDINGS' }),
+    ).rejects.toThrow(/duplicate key|unique/i);
+  });
+
+  itDb('allows same-name companies in different ports', async () => {
+    const portA = await makePort();
+    const portB = await makePort();
+    await makeCompany({ portId: portA.id, overrides: { name: 'Aegean Holdings' } });
+
+    await expect(
+      db.insert(companies).values({ portId: portB.id, name: 'Aegean Holdings' }),
+    ).resolves.toBeDefined();
+  });
+});