root@tts-0001:~# redis-cli
redis 127.0.0.1:6379> ping
PONG
redis 127.0.0.1:6379> select 1
OK
redis 127.0.0.1:6379[1]> select 16
(error) ERR invalid DB index
redis 127.0.0.1:6379[16]> select 0
OK
redis 127.0.0.1:6379> dbsize
(integer) 0
redis 127.0.0.1:6379> set cache ehcache
OK
redis 127.0.0.1:6379> dbsize
(integer) 1
redis 127.0.0.1:6379> set cache statClass
OK
redis 127.0.0.1:6379> dbsize
(integer) 1
redis 127.0.0.1:6379> keys *
1) "cache"
redis 127.0.0.1:6379> get cache
"statClass"
redis 127.0.0.1:6379> dbsize
(integer) 1
redis 127.0.0.1:6379> flushdb
OK
redis 127.0.0.1:6379> dbsize
(integer) 0
redis 127.0.0.1:6379> select 1
OK
redis 127.0.0.1:6379[1]> dbsize
(integer) 1
redis 127.0.0.1:6379[1]> keys *
1) "qiuchen"
redis 127.0.0.1:6379[1]> get qiuchen
"qiuchen"
redis 127.0.0.1:6379[1]> select 0
OK
redis 127.0.0.1:6379> flushall
OK
redis 127.0.0.1:6379> select 1
OK
redis 127.0.0.1:6379[1]> dbsize
(integer) 0