> ## Documentation Index > Fetch the complete documentation index at: https://api.buildingswell.com/llms.txt > Use this file to discover all available pages before exploring further. # Upsert a per diem code > Insert the per diem code, or update it when a row with a conflicting unique key already exists. `update` is required and lists which columns to overwrite on conflict. Matching is by `id` — the one in the path. If the `code` you send already belongs to a different entry, the request is rejected with `409`. ## OpenAPI ````yaml /openapi.yaml put /per-diem-code/{id} openapi: 3.0.3 info: title: BuildingSwell Public API version: 2.0.0 description: > The BuildingSwell v2 public API. Every request needs an `X-API-Key` header, and every key is scoped to one organization, so you only ever see your own data. Base URL: `https://app.buildingswell.com/api/v2` Most resources share the same CRUD and query shape. Read the [standard endpoints](/guides/standard-endpoints) and [querying](/guides/querying) guides once and the rest of this reference follows the same rules. For what a delete actually removes, see [archiving and deleting](/guides/archiving-and-deleting). servers: - url: https://{instance}/api/v2 description: Your BuildingSwell instance variables: instance: default: app.buildingswell.com description: Your BuildingSwell host security: - ApiKeyAuth: [] tags: - name: Projects description: Customer jobs, and the archive behavior they share with most resources. - name: Stages description: Reusable shop stations, scoped to a department. - name: Deliverables description: >- The work tree: orders, routes, phases, components, stages, steps, and QC steps. - name: Work sessions description: Time logged by one person against one deliverable. - name: Dependencies description: Scheduling links between deliverables. - name: Documents description: Files attached to orders. - name: QC description: QC templates and the inspection sets filled from them. - name: People (Workers) description: Your workforce roster. Called People in the app and `worker` in the API. - name: Timesheets description: Read-only view over attendance and work sessions. - name: Codes description: Cost, union, and per diem code lists. Referenced by value, not by id. - name: Roles description: Permission roles, and the statements that make them up. - name: Users description: >- People with a BuildingSwell login. Called Users in the app and `organization-member` in the API. - name: Concepts description: Deliverable writes with the nesting rules enforced. - name: Items description: Material and part definitions, purchasing units, and availability. - name: Item vendors description: Supplier SKUs linked to items. - name: Inventory stock description: Read-only quantities by item and location. - name: Inventory transactions description: The inventory ledger and its posting rules. - name: Inventory allocations description: Read-only reservations for orders and projects. - name: BOM lines description: Planned material inputs for routes, orders, and projects. - name: Production outputs description: Declarations of manufactured outputs. - name: Units of measure description: Reusable names and abbreviations for quantities. - name: Vendors description: Suppliers, manufacturers, and subcontractors. - name: Locations description: Department and project locations for storage and delivery. - name: Deliveries description: Inbound receipts, outbound trips, and transfers. - name: Delivery lines description: Material and ad-hoc manifest lines. - name: Trucks description: Fleet vehicles and their capacity. - name: Contacts description: Drivers, receivers, and other business contacts. - name: Project contacts description: Links between projects and contacts. - name: Teams description: Read-only department teams. - name: Shifts description: Read-only department shifts. - name: Departments (shops) description: Read-only departments, called shops in the API. - name: Custom properties description: Organization property definitions and values on orders. paths: /per-diem-code/{id}: put: tags: - Codes summary: Upsert a per diem code description: >- Insert the per diem code, or update it when a row with a conflicting unique key already exists. `update` is required and lists which columns to overwrite on conflict. Matching is by `id` — the one in the path. If the `code` you send already belongs to a different entry, the request is rejected with `409`. parameters: - $ref: '#/components/parameters/id' - $ref: '#/components/parameters/update' requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/CodeCreate' responses: '200': description: The upserted per diem code. content: application/json: schema: $ref: '#/components/schemas/CodeSingleResponse' '400': $ref: '#/components/responses/BadRequest' '401': $ref: '#/components/responses/Unauthorized' '403': $ref: '#/components/responses/Forbidden' '404': $ref: '#/components/responses/NotFound' '409': $ref: '#/components/responses/Conflict' '429': $ref: '#/components/responses/RateLimited' components: parameters: id: name: id in: path required: true description: Record id. schema: type: string format: uuid update: name: update in: query required: true description: >- Columns to overwrite when the row already exists. Repeat the parameter for each column: a single comma-separated value is read as one column name and fails at the database. Without the parameter the request is rejected with `400`. schema: type: array items: type: string style: form explode: true example: - name - costCode schemas: CodeCreate: type: object required: - code properties: id: type: string format: uuid description: Unique id. Generated on create unless you supply one. code: type: string description: >- The code value itself, for example `LOC-123`. Trimmed on write and unique within your organization for this list. minLength: 1 description: type: string description: What the code is for. Trimmed on write. Defaults to `null`. nullable: true isActive: type: boolean description: Whether the code is still offered for new work. Defaults to `true`. default: true createdAt: type: string format: date-time description: When the record was created. updatedAt: type: string format: date-time description: When the record last changed. CodeSingleResponse: type: object properties: value: $ref: '#/components/schemas/Code' required: - value Code: type: object description: >- One entry in a code list. Cost, union, and per diem codes are three separate lists that share this shape and behave identically. properties: id: type: string format: uuid description: Unique id. Generated on create unless you supply one. organizationId: type: string format: uuid description: >- Your organization. Taken from the API key, never from the request body. code: type: string description: >- The code value itself, for example `LOC-123`. Trimmed on write and unique within your organization for this list. This is the value that records reference, not the id. minLength: 1 description: type: string description: What the code is for. Trimmed on write. nullable: true isActive: type: boolean description: >- Whether the code is still offered for new work. Inactive codes stay valid on records that already carry them, and are still returned by the list endpoint unless you filter them out. default: true createdAt: type: string format: date-time description: When the record was created. updatedAt: type: string format: date-time description: When the record last changed. Error: type: object properties: error: type: object properties: message: type: string description: What went wrong, in plain language. code: type: string enum: - BAD_REQUEST - UNAUTHORIZED - FORBIDDEN - NOT_FOUND - CONFLICT - VALIDATION - UNIQUE_VIOLATION - FK_VIOLATION - RATE_LIMITED - INTERNAL description: >- Stable machine-readable code. Branch on this rather than on the message text. requestId: type: string description: Id for this request. Quote it when you contact support. details: type: array items: type: object description: One field-level problem. properties: path: type: string description: Field that failed, for example `data.stageId`. message: type: string description: Why it failed. code: type: string description: Validation code. description: Per-field problems. Present on validation failures only. missingPermissions: type: array items: type: string description: Permission name. description: Permissions your key is missing. Present on `403` only. context: type: object description: Extra context for the error. Usually empty. additionalProperties: true responses: BadRequest: description: >- The request was malformed or failed validation. Check `error.details` for the fields at fault. content: application/json: schema: $ref: '#/components/schemas/Error' Unauthorized: description: The `X-API-Key` header is missing or the key is invalid. content: application/json: schema: $ref: '#/components/schemas/Error' Forbidden: description: >- Your key lacks the permission for this call. `error.missingPermissions` lists what is needed. content: application/json: schema: $ref: '#/components/schemas/Error' NotFound: description: No record with that id in your organization. content: application/json: schema: $ref: '#/components/schemas/Error' Conflict: description: >- The write conflicts with existing data: a duplicate unique value (`UNIQUE_VIOLATION`), or a related record that blocks it (`FK_VIOLATION`). content: application/json: schema: $ref: '#/components/schemas/Error' RateLimited: description: >- Too many requests. Read `RateLimit-Reset` for when to retry. This response also carries a top-level `message` alongside `error`. content: application/json: schema: $ref: '#/components/schemas/Error' securitySchemes: ApiKeyAuth: type: apiKey in: header name: X-API-Key description: >- Organization-scoped API key. Create one in the BuildingSwell app under Organization settings, API keys. ````