How to filter Realm Results<Object> - ios

Question

I use mongoDB to store data. I have a Result array, which array contains multiple same keyword results.
class Keywords: Object {
#objc dynamic var name: String = ""
#objc dynamic var date: Date = Date()
#objc dynamic var rank: Int = 0
#objc dynamic var requestedURL: String = ""
}
Users can not send requests more than once for the same keyword name.
let action = UIAlertAction(title: "Add", style: .default) { action in
if let textSafe = text.text {
let textPrefix = textSafe.removeWhitespace()
if self.keywordModel.keywordNames.count > 0 {
if self.keywordModel.keywordNames.contains(textSafe) {
return
} else {
self.seo.fetchSEO(keyword: textPrefix, requestURL: self.selectedDomain!.domainName, start: 1)
}
} else {
self.seo.fetchSEO(keyword: textPrefix, requestURL: self.selectedDomain!.domainName, start: 1)
}
}
}
My codes are working fine up to this part.
But when users want to refresh to update results there I need to write filter results or somehow must get only the last recent results if keywords are multiple times stored in the database. By the way, I need multiplied keyword data results since I want to use them for date progress charts in the future.
So simply I need to save all results but I want to show only more recent results on UI.
#objc func refresh(_ sender: AnyObject) {
var keywordArray = [String]()
keywordModel.keywordNames.forEach { keyword in
keywordArray.append(keyword)
}
keywordModel.keywordNames = [String]()
keywordModel.keywordRanks = [Double]()
keywordArray.forEach { keyword in
self.seo.fetchSEO(keyword: keyword, requestURL: self.selectedDomain!.domainName)
}
print(keyword!)
let deadLine = DispatchTime.now() + .seconds(3)
DispatchQueue.main.asyncAfter(deadline: deadLine) {
self.refreshControl?.endRefreshing()
}
}
And for further detail, I transfer results to KeywordModel for some calculations, and i manage all tableview through the KeywordModel codes below.
struct KeywordModel {
var keywordRanks = [Double]()
var averageRank: Double? = 0.0
var keywordCount: Int? = 0
var keywordNames = [String]()
var keywordCountString: String? {
return String(keywordCount!)
}
var averageRankString: String? {
return String(format: "%.01f", averageRank!)
}
mutating func averageOfRanks(resultKeyword: Results<Keywords>?) {
keywordCount = resultKeyword?.count
var n = 0
var raw = [Double]()
while n < resultKeyword!.count {
raw.append(Double(resultKeyword![n].rank))
n += 1
}
keywordRanks = raw
let rankSum = keywordRanks.reduce(0, +)
averageRank = rankSum / Double(keywordRanks.count)
}
mutating func saveKeywords(from results: Results<Keywords>?) {
if results!.count > 0 {
var n = 0
var raw = [String]()
while n < results!.count {
raw.append(results![n].name)
n += 1
}
keywordNames = raw
}
}
And there is my loadData method, where I can apply a filter.
func loadData() {
keyword = selectedDomain?.keywords.sorted(byKeyPath: "name")
statisticCalculate(keyword: keyword)
tableView.reloadData()
}