How to Compile And Link SQLite

There are two main reasons to compile SQLite from source and they are both about getting features that are otherwise unavailable.

• You may need a feature from a release that haven't made it to your distro yet or you want to use the latest code from development.
• Perhaps you want some compile time features enabled that are not commonly enabled by default.

This guide assumes the first reason and goes through how to compile the latest release.

Install Prerequisites (Ubuntu)

On Ubuntu you will need build-essential installed at a minimum.

sudo apt update
sudo apt install build-essential

Download And Extract The Source Code

Source code for the latest release can be downloaded from the SQLite Download Page. Look for "C source code as an amalgamation", It should be the first one on the page.

wget https://sqlite.org/2021/sqlite-amalgamation-3370000.zip
unzip sqlite-amalgamation-3370000.zip
cd sqlite-amalgamation-3370000

Compile SQLite

Compile the sqlite command.

gcc shell.c sqlite3.c -lpthread -ldl -o sqlite3
./sqlite3 --version

Compile libsqlite.

gcc -lpthread -ldl -shared -o libsqlite3.so.0 -fPIC sqlite3.c

Using The New Version of SQLite

The path to libsqlite can be specified at runtime with "LD_LIBRARY_PATH".

# directory of your crystal app
cd ../app

# Crystal run
LD_LIBRARY_PATH=../sqlite-amalgamation-3370000 crystal run src/app.cr

# This way will allow specifying the library location at runtime if it is different from the system default.
crystal build --release --link-flags -L"$(realpath ../sqlite-amalgamation-3370000/libsqlite3.so.0)" src/app.cr
LD_LIBRARY_PATH=../sqlite-amalgamation-3370000 ./app

# ldd can be used to see which libsqlite is being linked
LD_LIBRARY_PATH=../sqlite-amalgamation-3370000 ldd ./app

Or the absolute path to libsqlite can be specified at compile time.

crystal run --link-flags "$(realpath ../sqlite-amalgamation-3370000/libsqlite3.so.0)" src/app.cr

# This will create a version that only works if libsqlite in the excact same location as when it was compiled.
crystal build --release --link-flags "$(realpath ../sqlite-amalgamation-3370000/libsqlite3.so.0)" src/app.cr
./app

# Use ldd to see which libsqlite is being linked
ldd ./app

Check SQLite Version From Crystal

To check which version of SQLite is being used from Crystal.

# src/app.cr

DB_URI = "sqlite3://:memory:"

DB.open DB_URI do |db|
    db_version = db.scalar "select sqlite_version();"
    puts "SQLite #{db_version}"
end