voluptasmollitia/docs-exp/firestore_.documentid.md

Monorepo for the Firebase JavaScript SDK

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## documentId() function

Returns a special sentinel `FieldPath` to refer to the ID of a document. It can be used in queries to sort or filter by the document ID.

<b>Signature:</b>

```typescript
export declare function documentId(): FieldPath;
```
<b>Returns:</b>

[FieldPath](./firestore_.fieldpath.md)