LevelDB is a library that implements a fast key-value store.
* Keys and values are arbitrary byte arrays.
* Data is stored sorted by key.
* Callers can provide a custom comparison function to override the sort order.
* The basic operations are Put(key,value), Get(key), Delete(key).
* Multiple changes can be made in one atomic batch.
* Users can create a transient snapshot to get a consistent view of data.
* Forward and backward iteration is supported over the data.
* Data is automatically compressed using the Snappy compression library.
* External activity (file system operations etc.) is relayed through a virtual interface so users can customize the operating system interactions.