根据App Engine 文档中的祖先查询,我可以执行以下操作:type Team struct { Name string}type Player struct { Name string}// Save data first just for the test caseteamA := datastore.NewIncompleteKey(c, "Team", nil)teamA, _ = datastore.Put(c, teamA, Team{"Team A"})playerA := datastore.NewIncompleteKey(c, "Player", teamA)playerA, _ = datastore.Put(c, playerA, Player{"Player A"})playerB := datastore.NewIncompleteKey(c, "Player", teamA)playerB , _ = datastore.Put(c, playerB, Player{"Player B"})// query dataq := datastore.NewQuery("Team").Filter("Name=", "Team A").Limit(1).KeysOnly()teams, _ := q.GetAll(c, nil)q = datastore.NewQuery("Player").Ancestor(teams[0])var players []Playerq.GetAll(c, &players)但是......如果我想让 Team 包含一个指向玩家切片的指针,那么我会将它保存为 nil,当我查询它时,我会分配它,有点像这样:type Team struct { Name string Players *[]Player `datastore:-`}type Player { Name string}// Save data first just for the test caseteamA := datastore.NewIncompleteKey(c, "Team", nil)teamA, _ = datastore.Put(c, teamA, Team{"Team A", nil})/* Saving player data goes here */// query dataq := datastore.NewQuery("Team").Filter("Name=", "Team A").Limit(1)var teams []TeamteamKeys, _ := q.GetAll(c, teams)q = datastore.NewQuery("Player").Ancestor(teamKeys[0])q.GetAll(c, teams[0].Players)这是模拟关系的好方法吗?对于我的应用程序,树状结构将是完美适合我手指的戒指。或者……你还有什么建议吗?
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