Comparison: Aurora PostgreSQL vs Neon

Modified date: Monday, June 30, 2025

Table of Contents

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

General

Feature	Aurora PostgreSQL	Neon	Definition
intro	Aurora is a relational database management system (RDBMS) built for the cloud with full MySQL and PostgreSQL compatibility.	Neon is a serverless open-source alternative to AWS Aurora Postgres. It separates storage and compute and substitutes the PostgreSQL storage layer by redistributing data across a cluster of nodes.	in their own words - but I reserved the rights to remove some bold claims like "the best", unless it is widely recognized.
vendor	Amazon AWS	Databricks
initial release		2021
latested version		8717	We don't put a release date here as the software is patching frequently. So tracking it is not much useful.
supported platforms		Linux and OSX Databricks acqured Neon on 05/2025	supported OS/CPU platforms
db-engines ranking		no ranking	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	mainly the engine code
license		Apache
cloud offering		cloud vendors
technical doc		https://neon.com/docs/introduction

Data Types

Feature	Aurora PostgreSQL	Neon	Definition
int: signess	signed only	signed only	if differentiate signed and unsigned int
int: 1-bytes int name	n.a.	n.a.
int: 2-bytes int name	smallint	smallint
int: 3-bytes int name	n.a.	n.a.
int: 4-bytes int name	int	int
int: 8-bytes int name	bigint	bigint
decimal: storage size	variable	variable
decimal: range	up to 131072 digits before the decimal point; up to 16383 digits after the decimal point	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	10,485,760
text: max bytes	1G	1G

SQL

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

Storage and System

Feature	Aurora PostgreSQL	Neon	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?		no	if multi-master support?
		Neon is based on PostgreSQL with storage and compute separation enhancement for native cloud DB.
arch: primary/read replica?		yes	if primary + mulitiple read replica supported
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

Benchmarking

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

Tools

Feature	Aurora PostgreSQL	Neon	Definition
command line client		psql	it means "sql client" for database supporting SQL. For embedded atabase, the client includes the server together.
admin(GUI)		pgAdmin

Export Regulations

Feature	Aurora PostgreSQL	Neon	Definition
Jurisdiction		US	Which country controls export
ECCN		None	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	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	Aurora PostgreSQL	Neon	Definition
concurrency control		MVCC
MVCC: implemented?		yes	if implement MVCC for concurrency control
Implementation language		Rust	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	Aurora PostgreSQL	Neon	Definition
CBO?		yes	if it employees a cost based optimizer
framework		System-R	System-R is more like a dynamic programming, bottom up optimizer, while Cascades/Volcano gebaseerd optimizer is more like top-down optimizer.
join order search		dynamic programming + Generic Algorithm (GEQO) reuse PostgreSQL's optimizer	How join order permutations are explored during plan generation.
stats: multi column		yes	Multi-column stats may cause storage space bloat: for example, if one dimension has 100 buckets, then three dimensions will require 1M buckets - but reducing the total number of buckets will result in reduced accuracy.
query hints?		GUC only	if it allows use query hints to guide the 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	Aurora PostgreSQL	Neon	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 run	The operator scheduling model: pull-gebaseerd (Volcano), push etc.
support intra-parallel query?		yes	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.
vectorization		no native	Speed up OLAP queries using vectorized execution. A vectorized runtime exchange a bunch of rows between iterators, and these rows are physically sotre with column-oriented order.
iterator: join methods		all 3	Hash Join (HJ), Sort-Merge Join (MJ) and Nested loop Join (NLJ) are 3 major ones
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.

Internal - Storage Engine

Feature	Aurora PostgreSQL	Neon	Definition