Write-once, read-many, minimal overhead binary structured file format.
Flatdata is a library providing data structures for convenient creation, storage and access of packed memory-mappable structures with minimal overhead.
With flatdata, the user defines a schema of the data format using a very simple schema language that supports plain structs, vectors and multivectors. The schema is then used to generate builders and readers for serialization and deserialization of the data to an archive of files on disk.
The data is serialized in a portable way which allows zero-overhead random access to it by using memory mapped storage: the operating system facilities are used for loading, caching and paging of the data, and most important, accessing it as if it were in memory.
Flatdata helps creating efficient read-only datasets:
- Zero overhead random access
- Support for bit and byte packing
- Structuring data using a schema definition
- Optimized for large read-only datasets
- Portable, with support for multiple languages
Flatdata doesn't provide:
- Backwards compatible schema evolution
- Support for mutable datasets
- Portable floating point serialization
For more details read why flatdata.
Define a flatdata archive:
namespace loc {
struct Point {
x : u32 : 32;
y : u32 : 32;
}
archive Locations {
pois : vector< Point >;
}
}The full schema documentation can be found here.
Flatdata relies on a generator that takes a flatdata schema file as an input and generates a module for one of the supported languages.
The following languages are supported:
- First-class citizen implementations:
- Read-only implementations:
See the generator's README for instructions.
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