lightdb is a lightweight disk-oriented relational database written in C++ which implements some key components of a traditional RDBMS including: Buffer Pool Manager (for memory management), Hash Index (storage engine), Query Executors & Query Optimizer (operators & optimizer), and Concurrency Control.

I created lightdb as a side-project in 2021 while learning database system at university and am in the process of migrating the code and docs to GitHub.

It is based on Dr Andy Pavlo's (@pavlo) BusTub database system template which is as simple as follows. The files inside src and test are empty and open to implementation using the super-useful tools and relevant third_party libraries.

bustub
├── build_support
│   ├── ...
├── src
│   ├── binder
│   ├── buffer
│   ├── catalog
│   ├── common
│   ├── concurrency
│   ├── container
│   ├── execution
│   ├── include
│   ├── optimizer
│   ├── planner
│   ├── primer
│   ├── recovery
│   ├── storage
│   └── type
├── test
│   ├── ...
├── third_party
│   ├── argparse
│   ├── backward-cpp
│   ├── cpp_random_distributions
│   ├── fmt
│   ├── googletest
│   ├── libfort
│   ├── libpg_query
│   ├── linenoise
│   ├── murmur3
│   ├── readerwriterqueue
│   ├── utf8proc
│   └── versions.txt
└── tools
    ├── b_plus_tree_printer
    ├── backtrace.cpp
    ├── bpm_bench
    ├── btree_bench
    ├── htable_bench
    ├── nc-shell
    ├── shell
    ├── sqllogictest
    ├── terrier_bench
    ├── wasm-bpt-printer
    └── wasm-shell

Build

It is preferred to build lightdb on Ubuntu 22.04, or macOS (M1/M2/Intel).

Linux (Recommended) / macOS (Development Only)

To ensure that you have the proper packages on your machine, run the following script to automatically install them:

# Linux
$ sudo build_support/packages.sh
# macOS
$ build_support/packages.sh

Then run the following commands to build the system:

$ mkdir build
$ cd build
$ cmake ..
$ make

If you want to compile the system in debug mode, pass in the following flag to cmake: Debug mode:

$ cmake -DCMAKE_BUILD_TYPE=Debug ..
$ make -j`nproc`

This enables AddressSanitizer by default.

If you want to use other sanitizers,

$ cmake -DCMAKE_BUILD_TYPE=Debug -DBUSTUB_SANITIZER=thread ..
$ make -j`nproc`

There are some differences between macOS and Linux (i.e., mutex behavior) that might cause test cases to produce different results in different platforms. We recommend students to use a Linux VM for running test cases and reproducing errors whenever possible.