YouTip

# Transaction executed successfully redis 127.0.0.1:6379> MULTI OK redis 127.0.0.1:6379> INCR user_id QUEUED redis 127.0.0.1:6379> INCR user_id QUEUED redis 127.0.0.1:6379> INCR user_id QUEUED redis 127.0.0.1:6379> PING QUEUED redis 127.0.0.1:6379> EXEC 1) (integer) 1 2) (integer) 2 3) (integer) 3 4) PONG # Key monitored, transaction executed successfully redis 127.0.0.1:6379> WATCH lock lock_times OK redis 127.0.0.1:6379> MULTI OK redis 127.0.0.1:6379> SET lock "huangz" QUEUED redis 127.0.0.1:6379> INCR lock_times QUEUED redis 127.0.0.1:6379> EXEC 1) OK 2) (integer) 1 # Key monitored, transaction interrupted redis 127.0.0.1:6379> WATCH lock lock_times OK redis 127.0.0.1:6379> MULTI OK redis 127.0.0.1:6379> SET lock "joe" QUEUED At this moment, another client modifies the value of lock_times redis 127.0.0.1:6379> INCR lock_times QUEUED redis 127.0.0.1:6379> EXEC Because lock_times was modified, Joe's transaction fails (nil) !(#)(#) AI Thoughts