redis 系列9 对象类型(字符串，哈希，列表，集合，有序集合)与数据结构关系

 typeof struct redisObject{
            //类型
            unsigned type:4;
            //编码
            unsigned encoding:4;
            //指向底层实现数据结构的指针
            void *ptr;

            //...
        }robj;

-- 值为字符串对象
127.0.0.1:6379> set msg "hello world"
OK
127.0.0.1:6379> type msg
string

-- 值为列表对象
127.0.0.1:6379> rpush number 1 3 5 
(integer) 3
127.0.0.1:6379> type number
list

-- 值为哈希对象    
127.0.0.1:6379> hmset profile name tom age 25 career programmer
OK
127.0.0.1:6379> type profile
hash

-- 值为集合对象
127.0.0.1:6379> sadd fruit apple banana cherry
(integer) 3
127.0.0.1:6379> type fruit
set

-- 值为有序集合对象
127.0.0.1:6379> zadd price 8.50 apple 3.30 banana
(integer) 2
127.0.0.1:6379> type price
zset    

127.0.0.1:6379> set msg "hello wrold"
OK
127.0.0.1:6379> object encoding msg
"embstr"

127.0.0.1:6379> set story "long long long long long long long long long ..."
OK
127.0.0.1:6379> object encoding story
"raw"
127.0.0.1:6379> sadd num 1 3 4
(integer) 0
127.0.0.1:6379> object encoding num
"intset"

127.0.0.1:6379> sadd num 1 3 4 "one"
(integer) 1
127.0.0.1:6379> object encoding num
"hashtable"

127.0.0.1:6379> zadd fruit-price 5.0 banana 6.5 cherry 8.0 apple
(integer) 0
127.0.0.1:6379> object encoding fruit-price
"ziplist"

127.0.0.1:6379> rpush integers "1" "2" "3" "4" "5" "6" "7" "8" "9" "10"
(integer) 20
127.0.0.1:6379> object encoding integers
"quicklist"