Key Value Database

Features

• This is Key Value store written in C# with implementation on native heap (has also prefix compression). InMemory version uses managed heap.
• It is easily embeddable.
• One storage is just one directory.
• It has ACID properties with MVCC.
• At one time there could be multiple read only transactions and one read/write transaction.
• Export/Import to stream - could be used for compaction, snapshotting
• Automatic compaction
• Customizable compression (key index file could be Brotli compressed)
• Relatively Fast DB Open due to key index file - though it still needs to load all keys to memory
• Inspired by Bitcask [https://github.com/basho/bitcask/blob/develop/doc/bitcask-intro.pdf]

Design limits

• All keys data needs to fit in RAM
• Maximum Key length is limited by 31bits (2GB).
• Maximum value length is limited by 31bits (2GB).

Sample code

Roadmap

• Everything is there just use it

Wrapped Dynamic IL generation with debugging + extensions

This help you to write fluent code which generates IL code in runtime. It is used in Object Database part.

Sample code

Roadmap

• Add support for all IL instructions as needed
• Deprecate this by replacing its usages by Source Generator

Object Database

Features

• Builds on top of Key Value Database and Reflection.Emit extensions.
• It stores Plain .Net Objects and only their public properties with getters and setters.
• All ACID and MVCC properties are preserved of course.
• Automatic upgrading of model on read with dynamically generated optimal IL code.
• Automatic versioning of model changes.
• Enumeration of all objects
• Each object type could store its "singleton" - very useful for root objects
• Relations - Table with primary key and multiple secondary keys
• By default objects are stored inline in parent object, use IIndirect for objects with Oid which will load lazily

Documentation: [https://github.com/Bobris/BTDB/blob/master/Doc/ODBDictionary.md]

Relations doc: [https://github.com/Bobris/BTDB/blob/master/Doc/Relations.md]

Sample code

Roadmap

• Support more types of properties
• Free text search (far future if ever)

Event storage

Features

• Optimal serialization with metadata
• Deserialization also to dynamic
• Storage is transactional
• As storage could be used Azure Page Blobs
• EventStorage2 is specialized to be used with Kafka, metadata are stored in separate topic

Bon

Bon Binary object notation is allows creating and reading JavaScript/C# values with extensions like Dictionary/Map into binary notation. It is much faster to parse, write, skip, search by keys than JSON, size will be also smaller in most cases, in some cases much more smaller.

Snappy Compression

Features

• Ported and inspired mainly by Go version of Snappy Compression [http://code.google.com/p/snappy/]
• Fully compatible with original
• Fully managed and safe implementation
• Compression is aborted when target buffer size is not big enough

Roadmap

• Some speed optimizations around Spans would help