Entity relationships - MUZE Architecture & Technical Documentation

Entity relationship diagram

Cascade behaviour

Parent	Child	On parent delete
`User`	`UserRole`, `Session`, `Account`, `Notification`	Cascade
`Employee`	`EmployeeSizeProfile`, `EntitlementPeriod`	Cascade
`EntitlementRuleSet`	`EntitlementRuleItem`, `EntitlementRuleCriteria`	Cascade
`Product`	`ProductSize`	Cascade
`Order`	`OrderItem`, `OrderStatusHistory`	Cascade

All other relations restrict deletes. That is why permanent deletes of stores, clients, or products run through batched transactions that remove dependent records first (the POST /<resource>/bulk-permanent endpoints).

Unique constraints

Model	Fields	Purpose
`User`	`email`	One account per email
`Session`	`token`	Session uniqueness
`Region`	`[clientId, code]`	Region codes per client
`Department`	`[clientId, code]`	Department codes per client
`Product`	`[clientId, code]`	Product codes per client
`ProductSize`	`[productId, value]`	One size value per product
`Employee`	`employeeNumber`	One record per employee number
`EmployeeSizeProfile`	`employeeId`	One profile per employee
`Store`	`storeNumber`	One record per store number
`StoreOrder`	`storeOrderNumber`	One batch number per submission
`Order`	`orderNumber`	Order number uniqueness
`SystemSetting`	`key`	One value per setting
`NumberSequence`	`key`	One counter per sequence

UserRole has no compound unique constraint; role assignment integrity is enforced by the service layer when creating accounts.

Index strategy

Prisma-managed indexes on the columns used by scoped queries:

Model	Indexed fields	Purpose
`Region`, `Department`, `UniformCategory`, `Product`	`clientId`	Client-scoped list queries
`Employee`	`storeId`, `uniformCategoryId`, `managerId`, `userId`	Store directory and category joins
`Order`	`employeeId`, `storeId`, `status`, `storeOrderId`	Order lists and batch grouping
`OrderItem`	`orderId`, `productId`, `entitlementPeriodId`	Consumption lookups
`EntitlementPeriod`	`[employeeId, periodType]`, `ruleSetId`	Balance and phase lookups
`EntitlementRuleItem`, `EntitlementRuleCriteria`	`ruleSetId`	Rule set expansion
`Notification`	`[recipientId, readAt]`	Unread badge queries
`AuditLog`	`actorId`, `[entityType, entityId]`	Audit filters