Question

我已将数据保存在Parse中存储组名的类中。每个组名称还具有包含所有组信息的关系。我试图查询关系中的数据，但输出没有产生任何结果。

第一个图像是包含组名称和组信息关系列的类（“组”），第二个图像是包含所有组数据的“GroupInfo”关系。

对象的保存方式如下：

let groups = PFObject(className: "Groups")
let groupinfo = PFObject(className: "Groupinfo")
@IBAction func CreateNewGroupAction(sender: AnyObject) {

    groupinfo["Score"] = 1
    groupinfo["Project"] = "Test"
    beaterinfo.save()


    groups["GroupName"] = "DFG"
 let relation = groups.relationForKey("Groupinfo")
    relation.addObject(groupinfo)

    beatergroups.save()

}

这是我尝试查询关系数据：

@IBAction func QueryDataAction(sender: AnyObject) {

    var groupnamesquery = PFQuery(className: "Groups")
  groupnamesquery.whereKey("GroupInfo", equalTo: "DFG")
    beatergroupnamesquery.findObjectsInBackgroundWithBlock { (object: [AnyObject]?, error: NSError?) -> Void in

        if error == nil && object != nil  {

            if let object = object as? [PFObject] {
                for objects in object {
                let relation = objects.relationForKey("GroupInfo")
               println(relation.valueForKey("Project")!)


                }

            }

        } else {

            println("Error: \(error)")
        }


    }



}

非常感谢任何有关查询关系数据的帮助！

Answer 1

“QueryDataAction”第二行出错：

groupnamesquery.whereKey("GroupInfo", equalTo: "DFG")

应该是

groupnamesquery.whereKey("**GroupName**", equalTo: "DFG")。

Answer 2

第一个查询仅返回不包含任何“GroupInfo”信息的“Groups”对象。因此，如果您执行嵌套查询，则应该能够检索GroupInfo对象。

@IBAction func QueryDataAction(sender: AnyObject) {

    var groupnamesquery = PFQuery(className: "Groups")
    groupnamesquery.whereKey("GroupName", equalTo: "DFG")
    beatergroupnamesquery.findObjectsInBackgroundWithBlock({ 
        (object: [AnyObject]?, error: NSError?) -> Void in
        if error == nil && object != nil  {
            if let object = object as? [PFObject] {
                for objects in object {

                    // create a relation based on the groupsinfo key
                    let relation = objects.relationForKey("GroupInfo")

                    // generate a query based on that relation
                    let query = relation.query()

                    // execute the query
                    let groupInfo = query.findObjects()

                    println(groupInfo["Project"])
                }
            }
        } else {
            println("Error: \(error)")
        }
    })
}

Answer 3

想出来：

@IBAction func QueryDataAction(sender: AnyObject) {

var groupnamesquery = PFQuery(className: "Groups")
groupnamesquery.whereKey("GroupName", equalTo: "DFG")
beatergroupnamesquery.findObjectsInBackgroundWithBlock({ 
    (object: [AnyObject]?, error: NSError?) -> Void in
    if error == nil && object != nil  {
        if let object = object as? [PFObject] {
            for objects in object {


                let relation = objects.relationForKey("GroupInfo")


                let query = relation.query()
  query?.findObjectsInBackgroundWithBlock({ (objecx: [AnyObject]?, erro: NSError?) -> Void in
                        if error == nil && objecx != nil {

                            if let objecx = objecx as? [PFObject] {
                                for obecxs in objecx {

                                let infos: AnyObject? = obecxs.valueForKey("Project")!

                                    println(infos!)
                                }


                            }

发出查询解析数据的问题

3 个答案: