# CollectionMember

object type

A collection member — ONE curated membership edge: a Product with a display ordinal inside a Collection. Parent = the Collection (members die with it). On a STATIC collection the members ARE the membership; on a DYNAMIC one they are the PINS (manual-pins-first — RC-o). Membership (collection x product) is unique (a live duplicate is CONFLICT/IDENTITY_TAKEN naming the holder); REMOVE = doom (TWO_STATE — history preserved); re-adding mints a NEW record via marker takeover.

## Fields

| Field | Type | Notes |
| --- | --- | --- |
| `id` | [ID](/types/#scalars) `ID!` | The record’s id — a UUID the platform assigned when the record was created; every reference to this record uses it. |
| `sysId` | [String](/types/#scalars) `String!` | The group-scoped human-facing system id (CM-…). |
| `type` | [String](/types/#scalars) `String!` | The kind of record — always `CollectionMember` here. |
| `caption` | [String](/types/#scalars) `String!` | The record’s display name — what people see it called. |
| `status` | [String](/types/#scalars) `String!` | The FSM state: active \| doomed. |
| `parentId` | [ID](/types/#scalars) `ID!` | The parent Collection; for a CollectionMember parentId!== rootId. |
| `rootId` | [ID](/types/#scalars) `ID!` | The org-group family root. |
| `createdAt` | [String](/types/#scalars) `String!` | When the record was created, as a UTC timestamp. |
| `updatedAt` | [String](/types/#scalars) `String!` | When the record last changed, as a UTC timestamp. |
| `revisionNum` | [Int](/types/#scalars) `Int!` | How many times this record has been edited; the first save is 0. |
| `revision` | [ID](/types/#scalars) `ID!` | The OCC revision token — supply it on every mutation of this record; rotates on every write. |
| `refCaptions` | [RefCaption](/types/RefCaption/) `[RefCaption!]!` | The server-composed captions of this record's declared references (the referenced-caption rule) — one row per referenced id; see RefCaption. |
| `productId` | [ID](/types/#scalars) `ID!` | The member Product — set at creation, IMMUTABLE thereafter. |
| `ordinal` | [Int](/types/#scalars) `Int!` | The display order. Mutable — reordering is an ordinary edit. |

## Used by

- [collectionMember](/reference/collection-member/collectionMember/)
- [createCollectionMember](/reference/collection-member/createCollectionMember/)
- [doomCollectionMember](/reference/collection-member/doomCollectionMember/)
- [updateCollectionMember](/reference/collection-member/updateCollectionMember/)