Redis多数据库

Redis多数据库

Redis默认有16个数据库，且都是用整数命名的，所以在测试环境和生产环境可以使用不同数据库

1    select index
切换到指定的数据库
2    move key db
将key移动到指定的数据库
3    dbsize
查看数据库中key的数量
4    info
查看数据库信息
5    flushdb 
清空当前数据库
6    flushall
清空所有数据库

eg：

#将set移到数据库db15中
127.0.0.1:6379> move set 15
(integer) 1
#进入db15数据库
127.0.0.1:6379> select 15
OK
查看所有key
127.0.0.1:6379[15]> keys *
1) "set"
#查看key的个数
127.0.0.1:6379[15]> dbsize
(integer) 1
#清空当前数据
127.0.0.1:6379[15]> flushdb
OK
127.0.0.1:6379[15]> dbsize
(integer) 0
查看数据库信息
127.0.0.1:6379[15]> info
# Server
redis_version:5.0.8
redis_git_sha1:00000000
redis_git_dirty:0
redis_build_id:ce75a617c591114f
redis_mode:standalone
os:Linux 3.10.0-957.el7.x86_64 x86_64
arch_bits:64
multiplexing_api:epoll
atomicvar_api:atomic-builtin
gcc_version:8.3.0
process_id:1
run_id:9c3a926cea0dec47fd83287a649884c891e87df8
tcp_port:6379
uptime_in_seconds:29558
uptime_in_days:0
hz:10
configured_hz:10
lru_clock:7894812
executable:/data/redis-server
config_file:

# Clients
connected_clients:4
client_recent_max_input_buffer:2
client_recent_max_output_buffer:0
blocked_clients:0

# Memory
used_memory:920168
used_memory_human:898.60K
used_memory_rss:10637312
used_memory_rss_human:10.14M
used_memory_peak:940208
used_memory_peak_human:918.17K
used_memory_peak_perc:97.87%
used_memory_overhead:892252
used_memory_startup:791264
used_memory_dataset:27916
used_memory_dataset_perc:21.66%
allocator_allocated:950688
allocator_active:1224704
allocator_resident:3985408
total_system_memory:5302657024
total_system_memory_human:4.94G
used_memory_lua:37888
used_memory_lua_human:37.00K
used_memory_scripts:0
used_memory_scripts_human:0B
number_of_cached_scripts:0
maxmemory:0
maxmemory_human:0B
maxmemory_policy:noeviction
allocator_frag_ratio:1.29
allocator_frag_bytes:274016
allocator_rss_ratio:3.25
allocator_rss_bytes:2760704
rss_overhead_ratio:2.67
rss_overhead_bytes:6651904
mem_fragmentation_ratio:12.11
mem_fragmentation_bytes:9759144
mem_not_counted_for_evict:0
mem_replication_backlog:0
mem_clients_slaves:0
mem_clients_normal:100460
mem_aof_buffer:0
mem_allocator:jemalloc-5.1.0
active_defrag_running:0
lazyfree_pending_objects:0

# Persistence
loading:0
rdb_changes_since_last_save:81
rdb_bgsave_in_progress:0
rdb_last_save_time:1584923558
rdb_last_bgsave_status:ok
rdb_last_bgsave_time_sec:-1
rdb_current_bgsave_time_sec:-1
rdb_last_cow_size:0
aof_enabled:0
aof_rewrite_in_progress:0
aof_rewrite_scheduled:0
aof_last_rewrite_time_sec:-1
aof_current_rewrite_time_sec:-1
aof_last_bgrewrite_status:ok
aof_last_write_status:ok
aof_last_cow_size:0

# Stats
total_connections_received:15
total_commands_processed:198
instantaneous_ops_per_sec:0
total_net_input_bytes:7847
total_net_output_bytes:31382
instantaneous_input_kbps:0.00
instantaneous_output_kbps:0.00
rejected_connections:0
sync_full:0
sync_partial_ok:0
sync_partial_err:0
expired_keys:0
expired_stale_perc:0.00
expired_time_cap_reached_count:0
evicted_keys:0
keyspace_hits:102
keyspace_misses:1
pubsub_channels:0
pubsub_patterns:1
latest_fork_usec:0
migrate_cached_sockets:0
slave_expires_tracked_keys:0
active_defrag_hits:0
active_defrag_misses:0
active_defrag_key_hits:0
active_defrag_key_misses:0

# Replication
role:master
connected_slaves:0
master_replid:a6b1ddde3d697f96d6b3e5b0951a9ad41c2dd1d4
master_replid2:0000000000000000000000000000000000000000
master_repl_offset:0
second_repl_offset:-1
repl_backlog_active:0
repl_backlog_size:1048576
repl_backlog_first_byte_offset:0
repl_backlog_histlen:0

# CPU
used_cpu_sys:22.428817
used_cpu_user:19.400454
used_cpu_sys_children:0.008691
used_cpu_user_children:0.002233

# Cluster
cluster_enabled:0

# Keyspace
db0:keys=10,expires=0,avg_ttl=0