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Redis入門一
Redis支持的數據類型：
- Binary-safe strings： 字符串
- Lists：有序列表；底層維護的是一個鏈表結構，包含字符串元素的集合，有順序、根據插入順序而定
- Sets ：無序集合；元素不可重複、無序 集合裏麵的元素是字符串
- Sorted sets：有序集合；和Sets 不同集合裏麵每個元素都關聯了一個 floating number value 叫做score， 集合會根據score來排序
- Hashes：散列；類似java的hashMap 由字段-字段值組成， 都是字符串。composed of fields associated with values. Both the field and the value are strings
- Bit arrays：
- HyperLogLogs
Redis keys 鍵值的選擇
- Very long keys are not a good idea 鍵值不能太長
- Very short keys are often not a good idea.鍵值太短也不太好
- Try to stick with a schema. 鍵值應該按照一種約定的模式來命名，如： "object-type:id" is a good idea, as in "user:1000". Dots or dashes are often used for multi-word fields, as in "comment:1234:reply.to" or "comment:1234:reply-to".多個單詞用點或者斜線分隔
- The maximum allowed key size is 512 MB.鍵值最長不能超過512 MB
Lists：Redis的Lists底層采用的是鏈表Link lists, 鏈表的優點：
1.插入速度快、時間複雜度是1 Redis Lists are implemented with linked lists because for a database system it is crucial to be able to add elements to a very long list in a very fast way. Another strong advantage, as you'll see in a moment, is that Redis Lists can be taken at constant length in constant time.
缺點：數據量大時訪問速度會慢，如果想要快的訪問速度可以采用 sort set
最後更新：2017-05-10 09:31:32