Minimalist nosql database system (WIP)
auto dal = Data_access_layer{"db.db", {page::Page::DEFAULT_PAGE_SIZE, 0.0125, 0.025}};
const auto collection_name = std::string{"collection1"};
auto collection = Collection{
&dal,
std::vector<uint8_t>{collection_name.begin(), collection_name.end()},
dal.meta.root};
for (uint32_t i = 1; i <= 6; i++)
{
const auto key = fmt::format("Key{}", i);
const auto value = fmt::format("Value{}", i);
collection
.put(
std::vector<uint8_t>{key.begin(), key.end()},
std::vector<uint8_t>{value.begin(), value.end()})
.map_error([&](const auto && error) { return error.panic(); });
}
const auto key1 = std::string{"Key1"};
const auto value1 = std::string{"Value1"};
collection.find(std::vector<uint8_t>{key1.begin(), key1.end()})
.map([&](const auto && item) {
CHECK_NE(item, tl::nullopt);
CHECK_EQ(
key1, std::string{item.value().key.begin(), item.value().key.end()});
CHECK_EQ(
value1,
std::string{item.value().value.begin(), item.value().value.end()});
})
.map_error([&](const auto && error) { return error.panic(); });
dal.close();
std::filesystem::remove(dal.path);This project is built with xmake, but it also provides cmake and makefile files generated by xmake, which is convenient for some users who don't have xmake installed.
This project was developed using gcc 14.2.0 and clang 18.1.8. In theory, the compiler should support C++ 20.
- git clone or download this project source code.
- cd or cd after unzip
xmake buildxmake test
- endian: C++ library for conversion between big and little endian data representations.
- optional: C++11/14/17 std::optional with functional-style extensions and reference support
- expected: C++11/14/17 std::expected with functional-style extensions
- spdlog: Fast C++ logging library.
The size of each page in toocal is the same as the operating system's virtual memory page size, but it also supports custom page size.
Page 0 and page 1 of toocal store the meta and freelist pages, which are used internally, so the real data will be stored starting from page 2.
toocal will serialize the internal data into files at a specific time, and all the data is in little endian order.
toocal uses a balanced binary tree for storage, which will help reduce the number of disk accesses.
Each node in the tree is a key-value pair, and they are stored on disk using slotted pages technology, which is a layout for organizing key value pairs of different sizes by positioning fixed sized offsets at the beginning and the actual data itself at the end.
Copyright (c) 2024 Muqiu Han
All rights reserved.
Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
* Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
* Neither the name of toocal nor the names of its contributors
may be used to endorse or promote products derived from this software
without specific prior written permission.
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