LevelDB是一套效率很高的嵌入式資料庫，本文的重點是將LevelDB移植到Android平台上。運用LevelDB的compact 機制，除了可以優化資料庫的讀取效能，也可以將整理過的資料轉換成檔案傳送至server。不同於往的復原或備份的機制，傳送的檔案會帶有資料庫的狀態、或刪除的資料。我們設定的情境為一個需要asynchronous 的環境，傳輸的頻率相對不用密集。可以在不用占用太多的網路頻寬之下，將較久之前的資料不定時的傳回server端。
LevelDB 會將資料整理成檔案，並將其從level-0開始擺放，隨著input的資料逐漸變多，查詢的次數增加，LevelDB 的compact機制將其逐漸將移動到高層。我們將移動到高層的檔案。做為傳送的目標。

關鍵字：LevelDB ；嵌入式資料庫系統

LevelDB is a highly efficient embedded database. The focus of this paper is to LevelDB ported to Android platform. LevelDB use compact mechanism to optimize reading performance. It can also be finishing off the data sent to server. We need to set a context for the asynchronous environment which the relative frequency of the transmission without intensive and take less of network bandwidth, and send the file which be operated before.
LevelDB will collated information into the file and store them at the level-0.After more operating, the result of file of compact will be move to the high level by mechanism of LevelDB's compact. and we sent the file in high level.

REFERENCES
[1] LevelDB compare with SQLite:http://vschart.com/compare/LevelDB/vs/sqlite.
[2] LevelDB benchmark :http://LevelDB.googlecode.com/svn/trunk/doc/benchmark.html
[3] LevelDB data follow http://brionas.github.io/2014/11/17/LevelDB-learning/
[4] LevelDB github https://github.com/google/LevelDB
[5] LevelDB Architecture http://www.cnblogs.com/haippy/archive/2011/12/04/2276064.html
[6] Fay Chang, ( 2006 )Bigtable: A Distributed Storage System for Structured Data, Google, Inc. Retrieved from : http://static.googleusercontent.com/media/research.google.com/zh-TW//archive/bigtable-osdi06.pdf
[7] LevelDB to use http://zhoutall.com/archives/579
[8] LevelDB write path:https://github.com/llhe/notes/blob/master/LevelDB/write-path.md
[9] LevelDB read path:https://github.com/llhe/notes/blob/master/LevelDB/read-path.md
[10] LevelDB compaction: https://github.com/llhe/notes/blob/master/LevelDB/compaction.md
[11] Android . http://developer.android.com/sdk/index.html
[12] Android transfer file by http. http://givemepass.blogspot.tw/2013/06/php-server.html