iOS如何针对数据库Parse Swift 4优化查询

Question

我有一个问题，如果更简短地说，我有连接到解析服务器的搜索模块。

在这个数据库中，我有50多个数据表，在其中存储了一些数据，对于搜索，我使用以下代码：

 func searchBarSearchButtonClicked(_ searchBar: UISearchBar) {
    searchBar.resignFirstResponder()
    searchResult.removeAll(keepingCapacity: false)
    answer.removeAll(keepingCapacity: false)
    tableView.reloadData()

    let firstQuery = PFQuery(className: "table1")
    firstQuery.whereKey("question", contains: searchBar.text)

    let seccondQuery = PFQuery(className: "table2")
    seccondQuery.whereKey("question", contains: searchBar.text)

    let query3 = PFQuery(className: "table3")
    query3.whereKey("question", contains: searchBar.text)

    let query4 = PFQuery(className: "table4")
    query4.whereKey("question", contains: searchBar.text)

    let queryArry = [firstQuery, seccondQuery, query3, query4]
    for query in queryArry {
        query.findObjectsInBackground { (result, error) in
            if let objects = result {
                for object in objects {
                    let question = object.object(forKey: "question") as! String
                    let answer = object.object(forKey: "answer1") as! String
                    self.answer.append(answer)
                    self.searchResult.append(question)

                }

                DispatchQueue.main.async {
                    self.tableView.reloadData()
                    self.resignFirstResponder()
                }
            }
        }

    }


}

如您所见，我有4个查询，还有一些我想改进的查询，因为每次我不想复制这部分代码时：

let firstQuery = PFQuery(className: "table1")
firstQuery.whereKey("question", contains: searchBar.text)

也许有一些改进的可能性吗？

Answer 1

如果您不想复制这部分代码

let firstQuery = PFQuery(className: "table1")
firstQuery.whereKey("question", contains: searchBar.text)

您可以执行以下操作：

let query1 = PFQuery(className: "table1")
let query2 = PFQuery(className: "table2")
let query3 = PFQuery(className: "table3")
let query4 = PFQuery(className: "table4")
let queries = [query1, query2, query3, query4]

queries.forEach { $0.whereKey("question", contains: searchBar.text) }
queries.forEach { (query) in
    query.findObjectsInBackground()
}

代码看起来更紧凑

希望我的回答对您有帮助