Features for GreenPlum

Modified date: Monday, June 30, 2025

Introduction
General
Data Types
SQL
Storage and System
Benchmarking
Tools
Export Regulations
Internal
Internal - Optimizer
Internal - Runtime
Internal - Storage Engine

Introduction

In its own words, "Tanzu Greenplum is a data warehouse, analytics and AI platform that allows you to unify all your data, transforming it into actionable insights and maintaining a single source of truth". It is currently ranked #48 in DB-Engine rankings.

Specific Concepts

We list some concpets might be used in the sections to explain things.

Concept	Explaination
GPORCA	Greenplum's query optimizer. It is based on Cascades framework, which is more assemble to SQL Sever's optimizer than PostgreSQL's native implementation.
GPOS	Greenplum's OS and infrastructure layer abstraction. What's interesting is, PostgreSQL does not have this layer but support more platforms than Greenplum.

General

Feature	Value	Definition
intro	Tanzu Greenplum is a data warehouse, analytics and AI platform that allows you to unify all your data, transforming it into actionable insights and maintaining a single source of truth	in their own words - but I reserved the rights to remove some bold claims like "the best", unless it is widely recognized.
vendor	VMWare
initial release	2005
latested version	7	We don't put a release date here as the software is patching frequently. So tracking it is not much useful.
supported platforms	Linux VMWare later acquired by Broadcom.	supported OS/CPU platforms
db-engines ranking	48	ranks from https://db-engines.com/en/ranking (06/25)
relational?	yes	Is it a relational database? (1) Most database are actually with some extensions, for example, nested data types, graph support, etc, which we usually called "multi-model". (2) Some of them are product family, meaning they have more than one database. Here we focus on the main one but explain others when needed.
open source?	yes (archieved)	mainly the engine code
license	Apache It is dual licensed. The archieved version (up to 05/24/24) is Apache. The commercial one is named Tanzu Greenplum by VMWare/BroadCom.
cloud offering	cloud vendors
technical doc	https://techdocs.broadcom.com/us/en/vmware-tanzu/data-solutions/tanzu-greenplum/7.html

Data Types

Feature	Value	Definition
int: signess	signed only	if differentiate signed and unsigned int
int: 1-bytes int name	n.a.
int: 2-bytes int name	smallint
int: 3-bytes int name	n.a.
int: 4-bytes int name	int
int: 8-bytes int name	bigint
decimal: storage size	variable
decimal: range	up to 131072 digits before the decimal point; up to 16383 digits after the decimal point	also called number, numeric in different systems
char(n): max bytes	10,485,760
text: max bytes	1G

SQL

Feature	Value	Definition
base	PostgreSQL
SQL: standard complaince	high
max SQL length	undefined same as PostgreSQL with "StringInfo" container	maximal SQL statement length
PL: main	SQL + PL/PgSQL	main programming lanage: most database suports SQL because SQL is a well established standard. However, each database would like to extend SQL more or less.
PL: other language support	yes	PL lanaguage other than PL/SQL, like PL/Java, PL/Rust etc
SP: max parameters	100
UDF: max parameters	100
SQL: max parameters	65535	number of parameters in a PREPARED query
SQL: query hints	GUC only	if it allows use query hints to guide the optimizer
SQL: explicit locking	yes: row, page, table level	Locking is usually an internal matter - so does it allow explicit locking? What levels do they support?
Triggers?	yes	If support triggers
Triggers: scope	tables, views, foreign tables	What objects can have triggers
Triggers: type	BEFORE, AFTER, INSTEAD OF	Types of triggers supported
Object-Relational?	yes
Extension Mechanism	C programming, link with engine
vector search	no native	does it support vector search

Storage and System

Feature	Value	Definition
arch: server	C/S	Embedded or traditional C/S?
arch: run in browser?	no	It also known as a client-side database, is a database that is stored and managed within a user's web browser, rather than on a remote server.
arch: in-memory support	no
arch: Multi-master support?	yes	if multi-master support?
	GreenPlum is based on PostgreSQL with massive OLAP processing enhancement: so MPP is its choice architecture.
replication: sync/async	both	Can commits wait or w/o wait for replicas to acknowledge
replication: WAL shipping	yes	Uses write-ahead log (WAL) shipping for replication
replication: quorum-based commit	no	Multiple synchronous replicas with quorum for commit

Benchmarking

Feature	Value	Definition
any official TPC benchmarks?	no	The TPC benchmark includes a set of tests simulating real-world scenarios to evaluate database performance.

Tools

Feature	Value	Definition
command line client	psql	it means "sql client" for database supporting SQL. For embedded atabase, the client includes the server together.

Export Regulations

Feature	Value	Definition
Jurisdiction	US	Which country controls export
ECCN	None/5D992	An Export Control Classification Number (ECCN) is a five-character alphanumeric code used to categorize items on the Commerce Control List (CCL) for export control purposes. Most database may fall into 5D992.c category, "mass market encryption", which means it has some ordinary encryption related code, for example, the SSL connection code.
Eligible License Exception / CCATS	Not required/ The open source license does not require a ECCN but the Tanzu commerical one needs 5D992.	A License Exception is an authorization that allows you to export or reexport items subject to the EAR without needing to obtain a specific export license, provided certain conditions are met. CCATS stands for Commodity Classification Automated Tracking System. The BIS assigns a CCATS number to products that it has classified under the Commerce Control List (CCL).
Encryption Components	SSL	Crypto functionality that triggers control

Internal

Feature	Value	Definition
concurrency control	MVCC
MVCC: implemented?	yes	if implement MVCC for concurrency control
Implementation language	C/C++ The PostgreSQL base code is in pure C but the extended part, including the GPOS, GPOrac(optimizer) are in C++.	A DBMS may use mulitple programming languages, for example, supports its stored procedure. The major programming language used to implement the engine.

Internal - Optimizer

Feature	Value	Definition
CBO?	yes	if it employees a cost based optimizer
framework	Cascades	System-R is more like a dynamic programming, bottom up optimizer, while Cascades/Volcano gebaseerd optimizer is more like top-down optimizer.
plan guide?	no	Can we use plan guide to correct the plan? This is a more systematic and accurate way to repair the plan than plan hints. Especially during system upgrades, if the plan becomes worse, we can use plan guide to force a query to use a previous plan.

Internal - Runtime

Feature	Value	Definition
resource management	simple: work_mem controls per-operator memory use	How execution memory is allocated and limited.
spilling support	yes	"spilling" refers to the process of writing temporary data or intermediate results of a query to disk when the available memory is exhausted. This is crucial for handling large datasets or complex queries that require more memory than available.
model	Volcano + push for parallel and distributed run	The operator scheduling model: pull-gebaseerd (Volcano), push etc.
support intra-parallel query?	no	meaning a single query can utilize multi hardware threads to run it
adaptive execution (AQP)?	no	Traditionally, after the optimizer determines the plan, the runtime must execute it completely without any room for adjustment, such as which of the two tables should be built. The adaptive method allows the runtime to make some adjustments based on the actual situation, and the optimizer must also prepare for this uncertainty, such as preparing an alternative plan.
Error: out-of-range and overflow	abort the transaction	To maintain atomic requirement of ACID, database engine usually fail the statement and abort the transaction.