PostgreSQL is a powerful, open-source object-relational database system that uses and extends the SQL language combined with many features that safely store and scale the most complicated data workloads.
The origins of PostgreSQL date back to 1986 as part of the POSTGRES project at Berkeley and has more than 35 years of active development on the core platform.
It has earned a strong reputation for its proven architecture, reliability, data integrity, robust feature set, extensibility, and the dedication of the open-source community behind the software to consistently deliver performant and innovative solutions.
It runs on all major operating systems, has been ACID-compliant since 2001, and has powerful add-ons such as the popular PostGIS geospatial database extender.

Data Types
- Primitives: Integer, Numeric, String, Boolean
- Structured: Date/Time, Array, Range / Multirange, UUID
- Document: JSON/JSONB, XML, Key-value (Hstore)
- Geometry: Point, Line, Circle, Polygon
- Customizations: Composite, Custom Types
Data Integrity
- UNIQUE, NOT NULL
- Primary Keys
- Foreign Keys
- Exclusion Constraints
- Explicit Locks, Advisory Locks
Concurrency, Performance
- Indexing: B-tree, Multicolumn, Expressions, Partial
- Advanced Indexing: GiST, SP-Gist, KNN Gist, GIN, BRIN, Covering indexes, Bloom filters
- Sophisticated query planner/optimizer, index-only scans, multicolumn statistics
- Transactions, Nested Transactions (via savepoints)
- Multi-Version Concurrency Control (MVCC)
- Parallelization of reading queries and building B-tree indexes
- Table partitioning
- All transaction isolation levels defined in the SQL standard, including Serializable
- Just-in-time (JIT) compilation of expressions
Reliability, Disaster Recovery
- Write-ahead Logging (WAL)
- Replication: Asynchronous, Synchronous, Logical
- Point-in-time-recovery (PITR), active standbys
- Tablespaces
Security
- Authentication: GSSAPI, SSPI, LDAP, SCRAM-SHA-256, Certificate, and more
- Robust access-control system
- Column and row-level security
- Multi-factor authentication with certificates and an additional method
Extensibility
- Stored functions and procedures
- Procedural Languages: PL/pgSQL, Perl, Python, and Tcl. There are other languages available through extensions, e.g. Java, JavaScript (V8), R, Lua, and Rust
- SQL/JSON path expressions
- Foreign data wrappers: connect to other databases or streams with a standard SQL interface
- Customizable storage interface for tables
- Many extensions that provide additional functionality, including PostGIS
Internationalisation, Text Search
- Support for international character sets, e.g., through ICU collations
- Case-insensitive and accent-insensitive collations
- Full-text search

Data Types

Number types

Name	Storage Size	Range
smallint	2 bytes	-32768 to +32767
integer	4 bytes	-2147483648 to +2147483647
bigint	4 bytes	-9223372036854775808 to 9223372036854775807
decimal	variable	up to 131072 digits before the decimal point; up to 16383 digits after the decimal point
numeric	variable	up to 131072 digits before the decimal point; up to 16383 digits after the decimal point
real	4 bytes	6 decimal digits precision
double	8 bytes	15 decimal digits precision

Serial Types

Name	Storage Size	Range
smallserial	2 bytes	1 to 32767
serial	4 bytes	1 to 2147483647
bigserial	8 bytes	1 to 9223372036854775807

Monetary Types

Name	Storage Size	Range
money	8 bytes	-92233720368547758.08 to 92233720368547758.07