Extensions can be built from source and installed from the resulting local binary.

Building Extensions Using Build Flags

To build using extension flags, set the CORE_EXTENSIONS flag to the list of extensions that you want to be buiold.

Extension will in most cases by directly linked the resulting DuckDB executable.

For example, to build DuckDB with the httpfs extension, run the following script:

GEN=ninja CORE_EXTENSIONS='httpfs' make

Special Extension Flags

BUILD_JEMALLOC

When this flag is set, the jemalloc extension is built.

BUILD_TPCE

When this flag is set, the TPCE libray is built. Unlike TPC-H and TPC-DS this is not a proper extension and it's not distributed as such. Enablign this allows TPC-E enabled queries through our test suite.

Debug Flags

CRASH_ON_ASSERT

D_ASSERT(condition) is used all throughout the code, these will throw an InternalException in debug builds. With this flag enabled, when the assertion triggers it will instead directly cause a crash.

DISABLE_STRING_INLINE

In our execution format string_t has the feature to “inline” strings that are under a certain length (12 bytes), this means they don't require a separate allocation. When this flag is set, we disable this and don't inline small strings.

DISABLE_MEMORY_SAFETY

Our data structures that are used extensively throughout the non-performance-critical code have extra checks to ensure memory safety, these checks include:

• Making sure nullptr is never dereferenced.
• Making sure index out of bounds accesses don't trigger a crash.

With this flag enabled we remove these checks, this is mostly done to check that the performance hit of these checks is negligible.

DESTROY_UNPINNED_BLOCKS

When previously pinned blocks in the BufferManager are unpinned, with this flag enabled we destroy them instantly to make sure that there aren't situations where this memory is still being used, despite not being pinned.

DEBUG_STACKTRACE

When a crash or assertion hit occurs in a test, print a stack trace. This is useful when debugging a crash that is hard to pinpoint with a debugger attached.

Using a CMake Configuration File

To build using a CMake configuration file, create an extension configuration file named extension_config.cmake with e.g., the following content:

duckdb_extension_load(autocomplete)
duckdb_extension_load(fts)
duckdb_extension_load(inet)
duckdb_extension_load(icu)
duckdb_extension_load(json)
duckdb_extension_load(parquet)

Build DuckDB as follows:

GEN=ninja EXTENSION_CONFIGS="extension_config.cmake" make

Then, to install the extensions in one go, run:

# for release builds
cd build/release/extension/
# for debug builds
cd build/debug/extension/
# install extensions
for EXTENSION in *; do
    ../duckdb -c "INSTALL '${EXTENSION}/${EXTENSION}.duckdb_extension';"
done