Greenplum Database (GPDB) is an advanced, fully featured, open source data warehouse, based on PostgreSQL. It provides powerful and rapid analytics on petabyte scale data volumes. Uniquely geared toward big data analytics, Greenplum Database is powered by the world’s most advanced cost-based query optimizer delivering high analytical query performance on large data volumes.

The Greenplum project is released under the Apache 2 license. We want to thank all our past and present community contributors and are really interested in all new potential contributions. For the Greenplum Database community no contribution is too small, we encourage all types of contributions.

Overview

A Greenplum cluster consists of a master server, and multiple segment servers. All user data resides in the segments, the master contains only metadata. The master server, and all the segments, share the same schema.

Users always connect to the master server, which divides up the query into fragments that are executed in the segments, and collects the results.

More information can be found on the project website.

Building Greenplum Database with GPORCA

GPORCA is a cost-based optimizer which is used by Greenplum Database in conjunction with the PostgreSQL planner. It is also known as just ORCA, and Pivotal Optimizer. The code for GPORCA resides src/backend/gporca. It is built automatically by default.

Installing dependencies (for macOS developers)

Follow these macOS steps for getting your system ready for GPDB

Installing dependencies (for Linux developers)

Follow appropriate linux steps for getting your system ready for GPDB

Build the database

# Configure build environment to install at /usr/local/gpdb
./configure --with-perl --with-python --with-libxml --with-gssapi --prefix=/usr/local/gpdb

# Compile and install
make -j8
make -j8 install

# Bring in greenplum environment into your running shell
source /usr/local/gpdb/greenplum_path.sh

# Start demo cluster
make create-demo-cluster
# (gpdemo-env.sh contains __PGPORT__ and __MASTER_DATA_DIRECTORY__ values)
source gpAux/gpdemo/gpdemo-env.sh

The directory, the TCP ports, the number of segments, and the existence of standbys for segments and coordinator for the demo cluster can be changed on the fly. Instead of make create-demo-cluster, consider:

DATADIRS=/tmp/gpdb-cluster PORT_BASE=5555 NUM_PRIMARY_MIRROR_PAIRS=1 WITH_MIRRORS=false make create-demo-cluster

The TCP port for the regression test can be changed on the fly:

PGPORT=5555 make installcheck-world

To turn GPORCA off and use Postgres planner for query optimization:

set optimizer=off;

If you want to clean all generated files

make distclean

Running tests

• The default regression tests

make installcheck-world

• The top-level target installcheck-world will run all regression tests in GPDB against the running cluster. For testing individual parts, the respective targets can be run separately.

• The PostgreSQL check target does not work. Setting up a Greenplum cluster is more complicated than a single-node PostgreSQL installation, and no-one's done the work to have make check create a cluster. Create a cluster manually or use gpAux/gpdemo/ (example below) and run the toplevel make installcheck-world against that. Patches are welcome!

• The PostgreSQL installcheck target does not work either, because some tests are known to fail with Greenplum. The installcheck-good schedule in src/test/regress excludes those tests.

• When adding a new test, please add it to one of the GPDB-specific tests, in greenplum_schedule, rather than the PostgreSQL tests inherited from the upstream. We try to keep the upstream tests identical to the upstream versions, to make merging with newer PostgreSQL releases easier.

Alternative Configurations

Building GPDB without GPORCA

Currently, GPDB is built with GPORCA by default. If you want to build GPDB without GPORCA, configure requires --disable-orca flag to be set.

# Clean environment
make distclean

# Configure build environment to install at /usr/local/gpdb
./configure --disable-orca --with-perl --with-python --with-libxml --prefix=/usr/local/gpdb

Building GPDB with gpperfmon enabled

gpperfmon tracks a variety of queries, statistics, system properties, and metrics. To build with it enabled, change your configure to have an additional option --enable-gpperfmon

See more information about gpperfmon here

gpperfmon is dependent on several libraries like apr, apu, and libsigar

Building GPDB with Python3 enabled

GPDB supports Python3 with plpython3u UDF

See how to enable Python3 for details.

Building GPDB client tools on Windows

See Building GPDB client tools on Windows for details.

Development with Docker

See README.docker.md.

We provide a docker image with all dependencies required to compile and test GPDB (See Usage).

Development with Vagrant

There is a Vagrant-based quickstart guide for developers.

Code layout

The directory layout of the repository follows the same general layout as upstream PostgreSQL. There are changes compared to PostgreSQL throughout the codebase, but a few larger additions worth noting:

• gpMgmt/

  Contains Greenplum-specific command-line tools for managing the cluster. Scripts like gpinit, gpstart, gpstop live here. They are mostly written in Python.

• gpAux/

  Contains Greenplum-specific release management scripts, and vendored dependencies. Some additional directories are submodules and will be made available over time.

• gpcontrib/

  Much like the PostgreSQL contrib/ directory, this directory contains extensions such as gpfdist and gpmapreduce which are Greenplum-specific.

• doc/

  In PostgreSQL, the user manual lives here. In Greenplum, the user manual is maintained separately and only the reference pages used to build man pages are here.

• gpdb-doc/

  Contains the Greenplum documentation in DITA XML format. Refer to gpdb-doc/README.md for information on how to build, and work with the documentation.

• ci/

  Contains configuration files for the GPDB continuous integration system.

• src/backend/cdb/

  Contains larger Greenplum-specific backend modules. For example, communication between segments, turning plans into parallelizable plans, mirroring, distributed transaction and snapshot management, etc. cdb stands for Cluster Database - it was a workname used in the early days. That name is no longer used, but the cdb prefix remains.

• src/backend/gpopt/

  Contains the so-called translator library, for using the GPORCA optimizer with Greenplum. The translator library is written in C++ code, and contains glue code for translating plans and queries between the DXL format used by GPORCA, and the PostgreSQL internal representation.

• src/backend/gporca/

  Contains the GPORCA optimizer code and tests. This is written in C++. See README.md for more information and how to unit-test GPORCA.

• src/backend/fts/

  FTS is a process that runs in the master node, and periodically polls the segments to maintain the status of each segment.

Contributing

See CONTRIBUTING.md