 
 private extension StatusesTable {
 
-	// MARK: Cache
+	// MARK: - Cache
 	
 	func articleIDsWithNoCachedStatus(_ articleIDs: Set<String>) -> Set<String> {
-
 		return Set(articleIDs.filter { cache[$0] == nil })
 	}
 
-	// MARK: Creating
+	// MARK: - Creating
 
 	func saveStatuses(_ statuses: Set<ArticleStatus>, _ database: FMDatabase) {
-
 		let statusArray = statuses.map { $0.databaseDictionary()! }
 		self.insertRows(statusArray, insertType: .orIgnore, in: database)
 	}
 
 	func createAndSaveStatusesForArticleIDs(_ articleIDs: Set<String>, _ read: Bool, _ database: FMDatabase) {
-
 		let now = Date()
 		let statuses = Set(articleIDs.map { ArticleStatus(articleID: $0, read: read, dateArrived: now) })
 		cache.addIfNotCached(statuses)

	}

	func fetchAndCacheStatusesForArticleIDs(_ articleIDs: Set<String>, _ database: FMDatabase) {
		
		guard let resultSet = self.selectRowsWhere(key: DatabaseKey.articleID, inValues: Array(articleIDs), in: database) else {
			return
		}

	}

	func add(_ statuses: Set<ArticleStatus>) {
		// Replaces any cached statuses.
		for status in statuses {
			self[status.articleID] = status
		}
	}

	func addStatusIfNotCached(_ status: ArticleStatus) {
		addIfNotCached(Set([status]))
	}
	
	func addIfNotCached(_ statuses: Set<ArticleStatus>) {
		// Does not replace already cached statuses.
		
		for status in statuses {
