This is a toydb, based on Chapter 3 : "Designing Data Intensive Applications" by Martin Kleppmann
- support simple get/put operations
- write the key-value in the file simpletoy.db
- each put appends to the file
- an in memory index stores the offset of the value
- the get operation seeks to the offset and reads the value
- file format : sequence<entry>'\n'
- entry format :
\<keysize\>\<keycontents\>\<valuesize\>\<valuecontents\> - support compaction
- delete older key values
- support delete, put tombstone to deleted value
- support multi segments of db file
- support SSTable, LSM tree
- support a B+Tree based implementation, for good sequential read performance