1. Install DarwinPorts, download DarwinPorts 1.3.2-archive.tar.gz, unzip it.
2. Copy unzipped folder to some location
3. cd to that location cd darwinports/base and run ./configure
5. sudo make install
6. Add export PATH=$PATH:/opt/local/bin to ~/.profile
7. Either logout of Mac or do source .profile
8. Run port sync
9. sudo port install rb-sqlite3
10.Run sqlite databasename in a shell. You will go to the sqlite command prompt.
You can now create tables and run sql queries. The advantage of this database is that it speeds up the testing during development. It is very fast.