快照读就是读取的是快照数据，不加锁的简单 Select 都属于快照读。

SELECT * FROM player WHERE ...
1
当前读就是读的是最新数据，而不是历史的数据。加锁的 SELECT，或者对数据进行增删改都会进行当前读。

SELECT * FROM player LOCK IN SHARE MODE;
SELECT FROM player FOR UPDATE;
INSERT INTO player values ...
DELETE FROM player WHERE ...
UPDATE player SET ...