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ObjectBox C / C++ Database

This is the ObjectBox documentation for our C and C++ APIs. We strive to provide you with the easiest and fastest solution to store and retrieve data.
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Latest Versions (Changelogs)

0.18.0 (2022-10-31)

  • Date properties can now be tagged as expiration time; which can be then be easily evicted
  • Tree API: various additions and improvements, e.g. OBXTreeOptionFlags to configure the tree behavior
  • New query condition to match objects that have a given number of relations
  • New "max data size" store setting
  • Enabled stricter compiler settings
  • Added stacktraces on errors (Linux only; very lightweight as it uses external addr2line or llvm-symbolizer)
  • Added log callback for most important logs
  • Consolidated "user data" passing as the last parameter
  • Various internal improvements

C++

  • Added BoxTypeless, QueryBuilderBase and QueryBase: these can be used without generated code and template types.
  • New APIs to get the schema IDs for entity types and properties
  • Added two methods to Store to await asynchronous processing
  • Added "internal" namespace so that internal members do not spill into the obx namespace
  • Move more implementations to OBX_CPP_FILE

Sync

  • Custom protocols for Sync: plugin your own messaging protocol, which ObjectBox Sync will run on
  • Improvements to run Sync Server with limited disk space (e.g. on small devices)
  • Tree Sync improvements; e.g. consolidate conflicts
  • WebSockets (sync protocol) is now a feature, which can be turned off (special build version)
  • Performance optimizations

0.17.0 (2022-06-15)

  • Added a "weak store" API providing weak reference for stores (typically used by background threads)
  • Added Store ID API, e.g. getting a store by its ID
  • Various internal improvements including minor optimizations for binary size and performance

C++

  • New "OBX_CPP_FILE" define to place declarations in a single .cpp/.cc file: improves compilation time and results
  • New "Exception" base class for all thrown exceptions
  • Various internal improvements, e.g. a "internal" namespace to better distinguish from userland API

0.16.0 (2022-05-06)

  • Allow UTF-8 for database directories on Windows (available for other platforms before)
  • Various internal improvements

C++

  • Promoted Options to a top level class, as nested classes cannot be declared forward
  • New #define to disable FlatBuffers includes to simplify new project setup
  • Rename Exception to DbException
  • Minor improvements

V0.15.2 (2022-02-15)

  • Add store cloning
  • Fix attaching to a reopened store

V0.15.1 (2022-01-26)

  • Fix non-unique indexes triggering unique constraint violations in corner cases (requires at least two unique constraints in an entity and a specific order; introduced in 0.15.0)
  • Admin UI now supports multiple sessions to the same host using different ports (session ID via HTTP request)
  • Minor performance improvements with hashed indexes

Sync

  • Performance improvements for compression and decompression

V0.15.0 (2021-12-09)

  • New "Flex" data type that can contain data of various types like integers, floating points, strings, lists and maps
  • New query conditions for Flex lists to find a specific element
  • New query conditions for Flex maps to find elements with a specific key or key/value pair
  • New unique on-conflict strategy: replace conflicting objects (OBXPropertyFlags_UNIQUE_ON_CONFLICT_REPLACE)
  • New functions to attach to existing stores using only the file path (in the same process)
  • New APIs for ObjectBox Admin, the web based UI (formerly known as Object Browser): obx_admin_*
  • Minor performance improvements for indexed access
  • Major performance improvements for tree/GraphQL queries
  • ARM binaries are now built for minimal size reducing the library size significantly
  • New "no_reader_thread_locals" store option
  • Enable debug logging (requires a special build)
  • API: Type for query offsets and limits was changed from uint64_t to size_t
  • API: rarely used obx_txn_mark_success() was removed; use obx_txn_success()
  • API: feature checks consolidated to only use obx_has_feature()
  • Many internal improvements
  • Core version 3.0.1-2021-12-09

Sync

  • New API for embedded server mode: obx_sync_server_* (implementation available on request)

Earlier Versions

The changelogs of earlier versions are available as part of the GitHub releases.
Provides native dynamic/shared library (.so/.dylib/.dll)
  • Provides C & C++ headers (objectbox.h & objectbox.hpp)

ObjectBox Generator

Check the ObjectBox Generator releases for details.
Last modified 1mo ago