2019独角兽企业重金招聘Python工程师标准>>> 
1.事务
1.1 MULTI和EXEC命令
发送MULTI命令，声明事务；EXEC执行事务
Redis不支持事务回滚
redis 127.0.0.1:6379> SET key 1
OK
redis 127.0.0.1:6379> SET key 2
OK
redis 127.0.0.1:6379> SADD key 3
(error) ERR Operation against a key holding the wrong kind of value
redis 127.0.0.1:6379> SADD key 3 4
(error) ERR Operation against a key holding the wrong kind of value
redis 127.0.0.1:6379> SADD keynew 3
(integer) 1
redis 127.0.0.1:6379> MUTIL
(error) ERR unknown command 'MUTIL'
redis 127.0.0.1:6379> MULTI
OK
redis 127.0.0.1:6379> SET key 3
QUEUED
redis 127.0.0.1:6379> SET keynew 4
QUEUED
redis 127.0.0.1:6379> EXEC
1) OK
2) OK
redis 127.0.0.1:6379> GET key
"3"
redis 127.0.0.1:6379> GET keynew
"4"
redis 127.0.0.1:6379>1.2 Watch命令
监控某个键值，如果被修改，阻止后面的事务执行。仅仅防御性质的。
redis 127.0.0.1:6379> SET key 1
OK
redis 127.0.0.1:6379> WATCH key
OK
redis 127.0.0.1:6379> MULTI
OK
redis 127.0.0.1:6379> SET key 2
QUEUED
redis 127.0.0.1:6379> EXEC
1) OK
redis 127.0.0.1:6379> GET key
"2"
redis 127.0.0.1:6379>redis 127.0.0.1:6379> SET keywatch 1
OK
redis 127.0.0.1:6379> SET keywatch 2
OK
redis 127.0.0.1:6379> WATCH keywatch
OK
redis 127.0.0.1:6379> SET keywatch 3
OK
redis 127.0.0.1:6379> MULTI
OK
redis 127.0.0.1:6379> SET keywatch 8
QUEUED
redis 127.0.0.1:6379> EXEC
(nil)
redis 127.0.0.1:6379> GET keywatch
"3"
redis 127.0.0.1:6379>