Method has

packages/db/src/collection/index.ts:487–489

* Check if a key exists in the collection (virtual derived state)

(key: TKey)

   * Check if a key exists in the collection (virtual derived state)
   */
  public has(key: TKey): boolean {
    return this._state.has(key)
  }

  /**
   * Get the current size of the collection (cached)