1.Python操作Redis：键(Key)

Python的redis模块管理键（Key）方法主要实现的Redis命令包括KEYS、GET、DEL（delete）、EXISTS、RANDOMKEY，TYPE、EXPIRE,其他的一些不能实现的在代码注释里面有所体现。

实验环境

Linux系统版本

LSB Version:    :base-4.0-amd64:base-4.0-noarch:core-4.0-amd64:core-4.0-noarch:graphics-4.0-amd64:graphics-4.0-noarch:printing-4.0-amd64:printing-4.0-noarch
Distributor ID: RedHatEnterpriseServer
Description:    Red Hat Enterprise Linux Server release 6.4 (Santiago)
Release:    6.4
Codename:   Santiago

Redis版本

127.0.0.1:6379> info
# Server
redis_version:3.0.7

Python版本

Python 2.6.6 (r266:84292, Jul 23 2015, 15:22:56)
[GCC 4.4.7 20120313 (Red Hat 4.4.7-11)] on linux2
Type "help", "copyright", "credits" or "license" for more information.

Python的Redis模块版本

DATA
__all__ = ['Redis', 'ConnectionPool', 'RedisError', 'ConnectionError',...
__version__ = '2.0.0'

VERSION
2.0.0

函数说明

set/get : 设置或者获取指定key的值，set/get key value

delete : 函数实现redis数据库DEL命令功能，delete key/DEL key

exists : 检测key存在与否，返回1或者0, exists key_name

expire : 设置过期时间，以秒计，expire key time

keys : 查找所有符合给定模式( pattern)的键 , keys pattern

type : 返回键(Key)对应的值, type key

randomKey : 返回当前数据库随机键对应的值，randomkey()/RANDOMKEY

由于Python的redis模块原因，Redis客户端有关键（KEY）的命令目前暂无可实现方法的代码事例。

代码示例

#!/usr/bin/python
import redis
import time
## Connect local redis service
client =redis.Redis(host='127.0.0.1',port=6379,db=0)
print "Connection to server successfully!"
dicKeys = client.keys("*")
print dicKeys

### Redis Key command part Start ###

# Set key-vlaue and get key-value
client.set('w3ckey','redis')
val = client.get('w3ckey')
print "Get key-vlaue ", val

# Delete key w3ckey
client.delete('w3ckey')
val = client.get('w3ckey')
print "Get none key-vlaue: ", val

# No dump key-value
client.set('greeting','Hello, dumping world!')
val = client.get('greeting')
print "Get key-vlaue ", val

# Exists check
keyList = ['w3ckey','greeting']
for key in keyList:
#    print "Key name: ",key
isKey =client.exists(key)
if isKey :
print "Have value mapping with key: ", key
else:
print "No value mapping with key: ",key
# Set Expire time for greeting
client.expire('greeting',2)
#saveTime = client.pttl('greeting')
#print "Remaining time: ",saveTime
time.sleep(2)
isExpire = client.get('greeting')
if not isExpire:
print "Key expire "
else:
print "Key not expire"

# Key get special pattern, Redis command:keys
#set value
keyDic = {'w3c1':'redis', 'w3c2':'mysql', 'w3c3':'mongodb'}
for key in keyDic.keys():
client.set(key,keyDic[key])
keyList = client.keys("w3c*")
print "Get keys: ",keyList

# Get random key from DB, Redis command:randomkey
randomKey =client.randomkey()
print "Get random key: ",randomKey

# Get key type, Redis command:type
keyType =client.type(randomKey)
print "Get key type: ",keyType

# Push value to list's head
client.lpush('w3ckey','redis')
client.lpush('w3ckey','mongodb')
client.lpush('w3ckey','mysql')
val = client.lrange('w3ckey',0,3)
print "Get key-vlaue list: ", val

#Empty db
client.flushdb()

hashVal = client.hgetall('profile')
print hashVal

参考资料

1、Redis 键(key)

2、Python redis文档（python交互模式下命令

>>>help redis

）