小编mag*_*1te的帖子

假设我每 2 秒执行一次查询，我应该在每个请求上打开连接，还是应该保持连接处于活动状态直到应用程序（服务器）停止？

我需要有关sql查询的帮助.

我有这两个表:

player_locations:

ID |  playerid  | location <- unqiue key
---|-----------------------
 1 |    1       | DOWNTOWN

和 users:

ID  | playername | [..]
----|--------------------
 1  | example1   | ...

我需要一个选择,以获得users.playername从player_locations.playerid.我有独特的地理位置player_locations.playerid.

伪查询:

SELECT playername 
FROM users
WHERE id = player_locations.playerid 
  AND player_locations.location = "DOWNTOWN";

输出应该是example1.