NoSQL

Histroy

• 2009-07-01: ​No to SQL? Anti-database movement gains steam
  • NoSQL 活動 - 漸漸有一股勢力在推動不要用 SQL Database .... 資料庫真的退流行了嗎??!! (2009-07-16)
  • 我個人的觀點是任何典範的轉移並不會一蹴可及，馬上轉換，往往是潛移默化，慢慢地改變。 (2009-07-27)
• NoSQL 會不會歷史重演 OODBMS ?! - ​Why Aren't You Using An OODMS? (2010-07-25)

  There was no great story on schema migration either. 
  

趨勢分析 Trend Observation

• ​比較 memcached, MongoDB, CouchDB, HBase, Apache Cassandra (2010-06-29)
• 

• 當然縱使 MongoDB 與 CouchDB 已經有很高的排行榜，跟 SQLite 比起來，還是差很多。 從 ​Google Trends 的搜尋趨勢可以看到 SQLite > Google Gears > CouchDB 的趨勢，象徵著 distributed database 的影響力尚未普及。 (2009-09-23)
  • 

• ​MongoDB, CouchDB, HBase, Cassandra, Hypertable 趨勢觀察 (2010-04-24)
  • 

• 從 ​2010 年 Google Trends 的搜尋趨勢可以看到 MongoDB 已經接近 Google Gears 了(當然跟 Google 宣布支援 HTML5 Local Database 有關). (2010-04-24)
  • 

Primer

• ​CAP Theorem
• ​ACID

Comparison

• ​Which databases solve my problem? a survey of open source databases - ​<note> Survey of Open Source Database - ​http://ossdbsurvey.org/
• ​HBase vs. Cassandra: NoSQL Battle!

Open Source Projects

• 2009-06-13: ​NOSQL debrief (2009-08-22)
• ​NOSQL - CouchDB (2009-08-11)
• ​NOSQL - Hypertable (2009-08-11)
• ​NOSQL - HBase (2009-08-11)
• ​Anti-RDBMS: A list of distributed key-value stores - 列舉出一些分散式 key-value 資料庫，不過漏了 (2009-09-23)
  • 噗浪的​lightcloud。
  • ​redis - A persistent key-value database with built-in net interface written in ANSI-C for Posix systems
    • ​Redis: Lightweight key/value Store That Goes the Extra Mile - 另一個輕量級的 Key/Value? 資料庫
• ​CouchDB -
  • ​Ubuntu couchdb 套件
  • ​Debian couchdb 套件
  • ​Modeling Entity Relationships in CouchDB
  • ​couchdb-fuse - CouchDB FUSE File System
  • [影片] ​Next Generation Data Storage with CouchDB (speaker: Jan Lehnardt) - Part 1
  • [影片] ​Next Generation Data Storage with CouchDB (speaker: Jan Lehnardt) - Part 2
  • [影片] ​MapReduce vs MySQL (speaker Stu Hood) - Part 1
  • [影片] ​MapReduce vs MySQL (speaker Stu Hood) - Part 2
  • [影片] ​MapReduce vs MySQL (speaker Stu Hood) - Part 3
  • 在看維基百科的時候，發現 CouchDB 同時被分屬在 ​Column-oriented DBMS 跟 ​Document-oriented database (2009-09-23)
  • ​Interactive CouchDB - 這裡用 Java Script 示範了 CouchDB 結合不同用途的 MapReduce 實作。
• ​dot.Cloud - an open-source cloud federation platform. - 從 Feature 看起來頗 Powerful (2009-09-23)
  • Keep your servers under revision control
  • Stop worrying about maintaining state: just create and kill instances
  • Use tools you know: rsync, mercurial/git, ssh
  • Push a small upgrade to your images without moving gigabytes around
  • Replicate multi-server setups in just one command
  • Cleanly separate data (DB, logs, content) and code (OS, libraries, binaries, configuration)
  • Map data volumes to any available storage (NAS, EBS, S3)
  • Save bandwidth by delivering your app closer to the consumer
• ​gears-dblib - A simple abstraction on top of the Database object in Gears (2009-09-23)
• ​orient - NoSQL document database light, portable and fast. Supports ACID Tx, Indexes, asynch queries, SQL layer, clustering, etc (2009-09-23)

NoSQL : HBase

• 11:10–12:00 Upcoming improvements for HBase - Andrew Purtell (Trend Micro) (2010-04-24)
  • Big Data -> Medium Data 都需要
  • Cloud Computing - Scale Free
  • Disk Seek time remains nearly constant -> Index(B-Tree), Seek (RMDB) 慢！！
  • No distributed transactions, no complex locking, no waits or deadlocks
  • 不要用 Spreadsheet 的想法看待 HBase, 或許可以用 Tag 的想法去看待它。
  • HBase 跟 BigTable 都是 CP 架構(注重 Consistancy 與 Partition Tolerance，根據 CAP Theorem 因此無法確保 Avaibility，寧可服務中斷也要資料正確！！)
  • HDFS-200 (working append) 將在 HBase 0.20.5 加入支援資料持續遞增的功能。
  • ACID ? - ​atomicity, consistency, isolation, durability
  • 新功能：
    • 跨資料中心備份 - 透過 Log Ship
    • 安全性強化 - 支援 authentication, authorization，Yahoo! 寫了很多新的安全性支援，包括 Kerberos 認證、Data isolation at the HDFS layer、Secure RPC。因此必須新增角色來作存取控管(Access Control Role)
    • Coprocessor - 靈感來自於 BigTable 的新功能 Coprocessor，加入 RegionObservor (需要再花點時間看清楚用途！！)

• 最近 waue 在投影片中用到一張新的 MapReduce 圖，今天再次在 Andrew 的演講中看到，出處是 Lars George 的部落格『​HBase MapReduce 101 - Part I』
  • 
• ​FOSDEM 2010 NoSQL Talk
  • ​FOSDEM NoSQL session
• ​HBase vs. CouchDB in Berlin

NoSQL : Cassandra

• ​Cassandra - a highly scalable, eventually consistent, distributed, structured key-value store. (2009-09-18)
  • ​Looking to the future with Cassandra
  • Cassandra was open sourced by Facebook in 2008
  • Cassandra brings together the distributed systems technologies from Dynamo and the data model from Google's BigTable.

• 09:00–09:50 nosql cassandra - Gasol (Pixnet) (2010-04-24)
  • ​http://cassandra.apache.org/
  • 具備副本機制，優先存在記憶體中，後續寫入 commit log 中。採取完全平等的分散式架構，沒有 Hadoop NameNode 單點失效問題(Single Point of Failure)
  • ​CAP theorem - Consistency (一致性), Availibility (可用性), Partition Tolerance (容錯性)三個勢必要犧牲其中一個！！

• 2010-03-02: ​4 Months with Cassandra, a love story - 用 Cassandra 的經驗分享 (2010-03-04)

NoSQL : Voldemort

• ​Voldemort - a distributed key-value storage system (2009-09-18)
  • used at LinkedIn for certain high-scalability storage problems

NoSQL : Redis

• ​Redis: Lightweight key/value Store That Goes the Extra Mile - 另一個輕量級的 Key/Value? 資料庫 (2009-09-02)

Use Case