redis中文手册：http://readthedocs.org/docs/redis/en/latest/?
本文是参考《redis中文手册》，将示例代码用php来实现，注意php-redis与redis_cli的区别（主要是返回值类型和参数用法）。
目录(使用CTRL+F快速查找命令)：
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phpredis是redis的php的一个扩展，效率是相当高有链表排序功能，对创建内存级的模块业务关系
很有用;以下是redis官方提供的命令使用技巧:
下载地址如下：
https://github.com/owlient/phpredis（支持redis 2.0.4）
Redis::__construct构造函数
$redis = new Redis();
connect, open 链接redis服务
参数
host: string，服务地址
port: int,端口号
timeout: float,链接时长 (可选, 默认为 0 ，不限链接时间)
注: 在redis.conf中也有时间，默认为300
pconnect, popen 不会主动关闭的链接
参考上面
setOption 设置redis模式
getOption 查看redis设置的模式
ping?查看连接状态
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KEY相关操作
DEL
移除给定的一个或多个key。
如果key不存在，则忽略该命令。
时间复杂度：O(N)，N为要移除的key的数量。
移除单个字符串类型的key，时间复杂度为O(1)。
移除单个列表、集合、有序集合或哈希表类型的key，时间复杂度为O(M)，M为以上数据结构内的元素数量。返回值：被移除key的数量。
KEYSKEYS pattern?查找符合给定模式的key。
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<span style="max-width:90%">//</span><span style="color: #008000; line-height: 1.5 !important;">DEL</span><span style="color: #008000; line-height: 1.5 !important;"> #</span><span style="color: #008000; line-height: 1.5 !important;"> 情况1： 删除单个key</span><span style="color: #800080; line-height: 1.5 !important;">$redis</span>->set('myname','ikodota'); <span style="color: #0000ff; line-height: 1.5 !important;">echo</span> <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->get('myname').'<br>'; <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 返回:ikodota</span> <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->del('myname');<span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 返回 TRUE(1)</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->get('myname')); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 返回 bool(false)</span> <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 情况2： 删除一个不存在的key</span><span style="color: #0000ff; line-height: 1.5 !important;">if</span>(!<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->exists('fake_key')) <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 不存在</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->del('fake_key')); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 返回 int(0)</span> <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 情况3： 同时删除多个key</span><span style="color: #800080; line-height: 1.5 !important;">$array_mset</span>=<span style="color: #0000ff; line-height: 1.5 !important;">array</span>('first_key'=>'first_val', 'second_key'=>'second_val', 'third_key'=>'third_val'); <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->mset(<span style="color: #800080; line-height: 1.5 !important;">$array_mset</span>); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;">用MSET一次储存多个值</span><span style="color: #800080; line-height: 1.5 !important;">$array_mget</span>=<span style="color: #0000ff; line-height: 1.5 !important;">array</span>('first_key','second_key','third_key'); <span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->mget(<span style="color: #800080; line-height: 1.5 !important;">$array_mget</span>)); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;">一次返回多个值 //array(3) { [0]=> string(9) "first_val" [1]=> string(10) "second_val" [2]=> string(9) "third_val" }</span> <span style="color: #800080; line-height: 1.5 !important;">$redis</span>-><strong>del</strong>(<span style="color: #800080; line-height: 1.5 !important;">$array_mget</span>); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;">同时删除多个key</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->mget(<span style="color: #800080; line-height: 1.5 !important;">$array_mget</span>)); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;">返回 array(3) { [0]=> bool(false) [1]=> bool(false) [2]=> bool(false) }</span>Copy after login
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KEYSKEYS pattern?查找符合给定模式的key。
KEYS?*命中数据库中所有key。
KEYS?h?llo命中hello，?hallo?and?hxllo等。
KEYS?h*llo命中hllo和heeeeello等。
KEYS?h[ae]llo命中hello和hallo，但不命中hillo。
特殊符号用"\"隔开
时间复杂度：O(N)，N为数据库中key的数量。返回值：符合给定模式的key列表。警告 :KEYS的速度非常快，但在一个大的数据库中使用它仍然可能造成性能问题，如果你需要从一个数据集中查找特定的key，你最好还是用集合(Set)。
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<span style="max-width:90%">//</span><span style="color: #008000; line-height: 1.5 !important;">KEYS</span><span style="color: #008000; line-height: 1.5 !important;"> #</span><span style="color: #008000; line-height: 1.5 !important;">$redis->FLUSHALL();</span><span style="color: #800080; line-height: 1.5 !important;">$array_mset_keys</span>=<span style="color: #0000ff; line-height: 1.5 !important;">array</span>('one'=>'1', 'two'=>'2', 'three '=>'3', 'four'=>'4'); <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->mset(<span style="color: #800080; line-height: 1.5 !important;">$array_mset_keys</span>); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;">用MSET一次储存多个值</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->keys('*o*')); <span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">array(3) { [0]=> string(4) "four" [1]=> string(3) "two" [2]=> string(3) "one" }</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->keys('t??')); <span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">array(1) { [0]=> string(3) "two" }</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->keys('t[w]*')); <span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">array(1) { [0]=> string(3) "two" }</span><span style="color: #008080; line-height: 1.5 !important;">print_r</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->keys('*')); <span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">Array ( [0] => four [1] => three [2] => two [3] => one )</span>Copy after login
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RANDOMKEY
从当前数据库中随机返回(不删除)一个key。
时间复杂度：O(1)返回值：当数据库不为空时，返回一个key。
当数据库为空时，返回nil。
TTL
TTL key
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<span style="max-width:90%">//</span><span style="color: #008000; line-height: 1.5 !important;">RANDOMKEY</span><span style="color: #800080; line-height: 1.5 !important;">$redis</span>->FLUSHALL(); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 情况1：数据库不为空</span><span style="color: #800080; line-height: 1.5 !important;">$array_mset_randomkey</span>=<span style="color: #0000ff; line-height: 1.5 !important;">array</span>('fruit'=>'apple', 'drink'=>'beer', 'food'=>'cookis'); <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->mset(<span style="color: #800080; line-height: 1.5 !important;">$array_mset_randomkey</span>); <span style="color: #0000ff; line-height: 1.5 !important;">echo</span> <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->randomkey(); <span style="color: #008080; line-height: 1.5 !important;">print_r</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->keys('*')); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 查看数据库内所有key，证明RANDOMKEY并不删除key//Array ( [0] => food [1] => drink [2] => fruit )</span> <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 情况2：数据库为空</span><span style="color: #800080; line-height: 1.5 !important;">$redis</span>->flushdb(); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 删除当前数据库所有key</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>-> randomkey()); <span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">bool(false)</span>Copy after login
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TTLTTL key
返回给定key的剩余生存时间(time to live)(以秒为单位)。
时间复杂度：O(1)返回值：
key的剩余生存时间(以秒为单位)。
当key不存在或没有设置生存时间时，返回-1?。
EXISTSEXISTS key
RENAMENX?RENAMENX key newkey
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<span style="max-width:90%">//</span><span style="color: #008000; line-height: 1.5 !important;">TTL</span><span style="color: #008000; line-height: 1.5 !important;"> #</span><span style="color: #008000; line-height: 1.5 !important;"> 情况1：带TTL的key</span><span style="color: #800080; line-height: 1.5 !important;">$redis</span>->flushdb(); <span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">$redis->set('name','ikodota'); # 设置一个key</span><span style="color: #800080; line-height: 1.5 !important;">$redis</span>->expire('name',30); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 设置生存时间为30秒 //return (integer) 1</span><span style="color: #0000ff; line-height: 1.5 !important;">echo</span> <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->get('name'); <span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">return ikodota</span><span style="color: #0000ff; line-height: 1.5 !important;">echo</span> <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->ttl('name'); <span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">(integer) 25//echo $redis->ttl('name'); # 30秒过去，name过期 //(integer) -1</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->get('name')); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 过期的key将被删除 //return bool(false);</span> <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 情况2：不带TTL的key</span><span style="color: #800080; line-height: 1.5 !important;">$redis</span>->set('site','wikipedia.org');<span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">OK</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->ttl('site'));<span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">int(-1)</span> <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 情况3：不存在的key</span><span style="color: #800080; line-height: 1.5 !important;">$redis</span>->EXISTS('not_exists_key');<span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">int(0)</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->TTL('not_exists_key'));<span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">int(-1)</span>Copy after login
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EXISTSEXISTS key检查给定key是否存在。
时间复杂度：O(1)返回值：若key存在，返回1，否则返回0。<span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">EXISTS</span><span style="color: #0000ff; line-height: 1.5 !important;">echo</span> '<br>EXISTS<br>'; <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->set('db',"redis"); <span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">bool(true) </span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->exists('db')); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> key存在 //bool(true) </span><span style="color: #800080; line-height: 1.5 !important;">$redis</span>->del('db'); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 删除key //int(1)</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->exists('db')) <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> key不存在 //bool(false)</span>Copy after login
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MOVE
MOVE key db
将当前数据库(默认为0)的key移动到给定的数据库db当中。
如果当前数据库(源数据库)和给定数据库(目标数据库)有相同名字的给定key，或者key不存在于当前数据库，那么MOVE没有任何效果。
因此，也可以利用这一特性，将MOVE当作锁(locking)原语。
时间复杂度：O(1)返回值：移动成功返回1，失败则返回0。<span style="max-width:90%">//</span><span style="color: #008000; line-height: 1.5 !important;">MOVE</span><span style="color: #0000ff; line-height: 1.5 !important;">echo</span> '<br><br>MOVE<br>'; <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 情况1： key存在于当前数据库</span><span style="color: #800080; line-height: 1.5 !important;">$redis</span>->SELECT(0); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> redis默认使用数据库0，为了清晰起见，这里再显式指定一次。//OK</span><span style="color: #800080; line-height: 1.5 !important;">$redis</span>->SET('song',"secret base - Zone"); <span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">OK</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span> (<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->MOVE('song',1)); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 将song移动到数据库1 //bool(true)</span> <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 情况2：当key不存在的时候</span><span style="color: #800080; line-height: 1.5 !important;">$redis</span>->SELECT(1); <span style="color: #008080; line-height: 1.5 !important;">var_dump</span> (<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->EXISTS('fake_key'));<span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">bool(false);</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->MOVE('fake_key', 0)); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 试图从数据库1移动一个不存在的key到数据库0，失败) //bool(false)</span> <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->SELECT(0); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 使用数据库0</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->EXISTS('fake_key')); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 证实fake_key不存在 //bool(false)</span> <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 情况3：当源数据库和目标数据库有相同的key时</span> <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->SELECT(0); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 使用数据库0</span><span style="color: #800080; line-height: 1.5 !important;">$redis</span>->SET('favorite_fruit',"banana"); <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->SELECT(1); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 使用数据库1</span><span style="color: #800080; line-height: 1.5 !important;">$redis</span>->SET('favorite_fruit',"apple"); <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->SELECT(0); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 使用数据库0，并试图将favorite_fruit移动到数据库1</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->MOVE('favorite_fruit',1)); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 因为两个数据库有相同的key，MOVE失败 //return bool(false)</span><span style="color: #0000ff; line-height: 1.5 !important;">echo</span> <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->GET('favorite_fruit'); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 数据库0的favorite_fruit没变 //return banana</span> <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->SELECT(1); <span style="color: #0000ff; line-height: 1.5 !important;">echo</span> <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->GET('favorite_fruit'); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 数据库1的favorite_fruit也是 //return apple</span>Copy after login
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RENAME?
将key改名为newkey。
当key和newkey相同或者key不存在时，返回一个错误。
当newkey已经存在时，RENAME命令将覆盖旧值。
时间复杂度：O(1)返回值：改名成功时提示OK，失败时候返回一个错误。<span style="max-width:90%">//</span><span style="color: #008000; line-height: 1.5 !important;">RENAME</span><span style="color: #0000ff; line-height: 1.5 !important;">echo</span> '<br><br>RENAME<br>'; <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 情况1：key存在且newkey不存在</span><span style="color: #800080; line-height: 1.5 !important;">$redis</span>->SET('message',"hello world"); <span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>-><span style="color: #008080; line-height: 1.5 !important;">RENAME</span>('message','greeting')); <span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">bool(true)</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->EXISTS('message')); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> message不复存在 //bool(false)</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->EXISTS('greeting')); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> greeting取而代之 //bool(true)</span> <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 情况2：当key不存在时，返回错误 ,php返回false;</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>-><span style="color: #008080; line-height: 1.5 !important;">RENAME</span>('fake_key','never_exists')); <span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">bool(false)</span> <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 情况3：newkey已存在时，RENAME会覆盖旧newkey</span><span style="color: #800080; line-height: 1.5 !important;">$redis</span>->SET('pc',"lenovo"); <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->SET('personal_computer',"dell"); <span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>-><span style="color: #008080; line-height: 1.5 !important;">RENAME</span>('pc','personal_computer')); <span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">bool(true)</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->GET('pc')); <span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">(nil) bool(false)</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->GET('personal_computer')); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> dell“没有”了 //string(6) "lenovo"</span>Copy after login
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RENAMENX?RENAMENX key newkey当且仅当newkey不存在时，将key改为newkey。
出错的情况和RENAME一样(key不存在时报错)。
时间复杂度：O(1)返回值：修改成功时，返回1。
如果newkey已经存在，返回0。
TYPETYPE key
<span style="max-width:90%">//</span><span style="color: #008000; line-height: 1.5 !important;">RENAMENX</span><span style="color: #0000ff; line-height: 1.5 !important;">echo</span> '<br><br>RENAMENX<br>'; <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 情况1：newkey不存在，成功</span><span style="color: #800080; line-height: 1.5 !important;">$redis</span>->SET('player',"MPlyaer"); <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->EXISTS('best_player'); <span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">int(0)</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->RENAMENX('player','best_player')); <span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;"> bool(true) </span> <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 情况2：newkey存在时，失败</span><span style="color: #800080; line-height: 1.5 !important;">$redis</span>->SET('animal',"bear"); <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->SET('favorite_animal', "butterfly"); <span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->RENAMENX('animal', 'favorite_animal'));<span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;"> bool(false)</span> <span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->get('animal')); <span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">string(4) "bear"</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->get('favorite_animal')); <span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">string(9) "butterfly"</span>Copy after login
TYPETYPE key返回key所储存的值的类型。
时间复杂度：O(1)返回值：
none(key不存在) int(0)
string(字符串) int(1)
list(列表) int(3)
set(集合) int(2)
zset(有序集) int(4)
hash(哈希表) int(5)
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<span style="max-width:90%">//</span><span style="color: #008000; line-height: 1.5 !important;">TYPE</span><span style="color: #800080; line-height: 1.5 !important;">$redis</span>->flushALL(); <span style="color: #0000ff; line-height: 1.5 !important;">echo</span> '<br><br>TYPE<br>'; <span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->TYPE('fake_key')); <span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">none /int(0)</span> <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->SET('weather',"sunny"); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 构建一个字符串</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->TYPE('weather'));<span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">string / int(1)</span> <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->SADD('pat',"dog"); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 构建一个集合</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->TYPE('pat')); <span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">set /int(2)</span> <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->LPUSH('book_list',"programming in scala"); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 构建一个列表</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->TYPE('book_list'));<span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">list / int(3) </span> <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->ZADD('pats',1,'cat'); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 构建一个zset (sorted set) // int(1)</span><span style="color: #800080; line-height: 1.5 !important;">$redis</span>->ZADD('pats',2,'dog'); <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->ZADD('pats',3,'pig'); <span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->zRange('pats',0,-1)); <span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;"> array(3) { [0]=> string(3) "cat" [1]=> string(3) "dog" [2]=> string(3) "pig" }</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->TYPE('pats')); <span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">zset / int(4)</span> <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->HSET('website','google','www.g.cn'); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 一个新域</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->HGET('website','google')); <span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">string(8) "www.g.cn"</span><span style="color: #008080; line-height: 1.5 !important;">var_dump</span>(<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->TYPE('website')); <span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">hash /int(5)</span>Copy after login
EXPIRE
EXPIRE key seconds
为给定key设置生存时间。
当key过期时，它会被自动删除。
在Redis中，带有生存时间的key被称作“易失的”(volatile)。
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在低于2.1.3版本的Redis中，已存在的生存时间不可覆盖。
从2.1.3版本开始，key的生存时间可以被更新，也可以被PERSIST命令移除。(详情参见?http://redis.io/topics/expire)。
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时间复杂度：O(1)返回值：设置成功返回1。
当key不存在或者不能为key设置生存时间时(比如在低于2.1.3中你尝试更新key的生存时间)，返回0。
EXPIREAT?EXPIREAT key timestamp
<span style="max-width:90%">//</span><span style="color: #008000; line-height: 1.5 !important;">EXPIRE</span><span style="color: #800080; line-height: 1.5 !important;">$redis</span>->select(7); <span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">$redis->flushdb();</span> <span style="color: #0000ff; line-height: 1.5 !important;">echo</span> '<br><br>EXPIRE<br>'; <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->SET('cache_page',"www.cnblogs.com/ikodota"); <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->EXPIRE('cache_page', 30); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 设置30秒后过期</span><span style="color: #008080; line-height: 1.5 !important;">sleep</span>(6); <span style="color: #0000ff; line-height: 1.5 !important;">echo</span> <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->TTL('cache_page').'<br>'; <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 查看给定key的剩余生存时间 //(integer) 24</span> <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->EXPIRE('cache_page', 3000); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 更新生存时间，3000秒</span><span style="color: #008080; line-height: 1.5 !important;">sleep</span>(4); <span style="color: #0000ff; line-height: 1.5 !important;">echo</span> <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->TTL('cache_page').'<br>'; <span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">(integer) 2996</span>Copy after login
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EXPIREAT?EXPIREAT key timestampEXPIREAT的作用和EXPIRE一样，都用于为key设置生存时间。
不同在于EXPIREAT命令接受的时间参数是UNIX时间戳(unix timestamp)。
时间复杂度：O(1)返回值：如果生存时间设置成功，返回1。
当key不存在或没办法设置生存时间，返回0。
OBJECT?OBJECT subcommand [arguments [arguments]]
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<span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">EXPIREAT</span><span style="color: #0000ff; line-height: 1.5 !important;">echo</span> '<br><br>EXPIREAT<br>'; <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->SET('cache','www.google.com'); <span style="color: #0000ff; line-height: 1.5 !important;">echo</span> <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->EXPIREAT('cache','1355292000'); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #008000; line-height: 1.5 !important;"> 这个key将在2012.12.12过期</span> <span style="color: #0000ff; line-height: 1.5 !important;">echo</span> (<span style="color: #800080; line-height: 1.5 !important;">$redis</span>->TTL('cache')); <span style="color: #008000; line-height: 1.5 !important;">//</span><span style="color: #008000; line-height: 1.5 !important;">return 124345085</span>Copy after login
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OBJECT?OBJECT subcommand [arguments [arguments]]OBJECT命令允许从内部察看给定key的Redis对象。
它通常用在除错(debugging)或者了解为了节省空间而对key使用特殊编码的情况。
当将Redis用作缓存程序时，你也可以通过OBJECT命令中的信息，决定key的驱逐策略(eviction policies)。
OBJECT命令有多个子命令：
-
OBJECT?REFCOUNT?
返回给定key引用所储存的值的次数。此命令主要用于除错。 -
OBJECT?ENCODING?
返回给定key锁储存的值所使用的内部表示(representation)。 -
OBJECT?IDLETIME?
返回给定key自储存以来的空转时间(idle， 没有被读取也没有被写入)，以秒为单位。
对象可以以多种方式编码：
- 字符串可以被编码为raw(一般字符串)或int(用字符串表示64位数字是为了节约空间)。
- 列表可以被编码为ziplist或linkedlist。ziplist是为节约大小较小的列表空间而作的特殊表示。
- 集合可以被编码为intset或者hashtable。intset是只储存数字的小集合的特殊表示。
- 哈希表可以编码为zipmap或者hashtable。zipmap是小哈希表的特殊表示。
- 有序集合可以被编码为ziplist或者skiplist格式。ziplist用于表示小的有序集合，而skiplist则用于表示任何大小的有序集合。
假如你做了什么让Redis没办法再使用节省空间的编码时(比如将一个只有1个元素的集合扩展为一个有100万个元素的集合)，特殊编码类型(specially encoded types)会自动转换成通用类型(general type)。时间复杂度：O(1)返回值：
REFCOUNT和IDLETIME返回数字。
ENCODING返回相应的编码类型。
<span style="max-width:90%">//</span><span style="color: #008000; line-height: 1.5 !important;">OBJECT</span><span style="color: #800080; line-height: 1.5 !important;">$redis</span>->select(8); <span style="color: #0000ff; line-height: 1.5 !important;">echo</span> '<br><br>OBJECT<br>'; <span style="color: #800080; line-height: 1.5 !important;">$redis</span>->SET('game',"WOW"); <span style="color: #008000; line-height: 1.5 !important;">#</span><span style="color: #00"></span>Copy after login
