question

Please note that the Title data is suitable for storing global constant/static data instead of the data which changes frequently. Because Title data values are copied and distributed to potentially hundreds of machines in the PlayFab server cluster. As part of this process, Title Data is cached, and changes may take up to fifteen minutes to refresh in those caches. In your case, you want to get the player's Rank info when the player logs in, so that you can reduce the extra API calls to retrieve it. So, you can store the Rank info into the player read only data, and when players calls the login API, he can retrieve the specified player read only data via setting InfoRequestParameters. You can refer to my testing request body of login API below. In addition, if the player's ranking information is subject to change at any time, it may not be accurate to retrieve the previously stored rank information by retrieving player read only data when the player logs in. In this case, you may need to call an additional API to retrieve the real-time ranking of players after logging in.

 {
   "CustomId": "Yan",
   "CreateAccount": false,
   "TitleId": "   ",
   "InfoRequestParameters":{
     "GetUserReadOnlyData":true,
     "UserReadOnlyDataKeys":["Rank"]
     }
 }