Alibaba Cloud has launched PostgreSQL 18 support in its PolarDB service, making it one of the first major cloud platforms to offer the latest open-source database version. PostgreSQL 18 was officially released by the PostgreSQL Global Development Group on September 25, 2025, introducing asynchronous I/O, improved indexing, and native UUIDv7 support. PolarDB for PostgreSQL 18 is available now via a whitelist approval process, with general availability expected after PostgreSQL 18.1 stabilizes.
What’s New in PostgreSQL 18
PostgreSQL 18 introduces an asynchronous I/O subsystem that allows backend processes to handle multiple read requests simultaneously. This enhancement improves sequential scans, bitmap heap scans, and VACUUM operations by up to 3× in early benchmarks. The new io_method parameter controls this behavior, and a pg_aios system view exposes file handles used for async I/O.
The query optimizer received significant upgrades, automatically removing unnecessary self-joins and transforming IN (VALUES) expressions into x = ANY() for better statistics. PostgreSQL 18 adds skip scan support for B-tree indexes, enabling queries to use non-leading columns in multi-column indexes more efficiently. Parallel GIN index creation is now supported, accelerating full-text and JSON indexing workflows.
PostgreSQL 18 introduces native UUIDv7 support, which generates timestamp-ordered UUIDs that improve database indexing performance compared to random UUIDs. Virtual generated columns compute values on read rather than storing them, reducing storage overhead. The RETURNING clause now accepts OLD and NEW references, allowing INSERT, UPDATE, DELETE, and MERGE statements to return both original and modified row values.
How PolarDB for PostgreSQL 18 Differs
PolarDB for PostgreSQL uses a compute-storage separation architecture where all nodes share the same distributed storage layer. This design enables clusters to scale compute resources within five minutes without data migration. The service supports one primary node and up to 15 read-only nodes, delivering over 500,000 read requests per second and 150,000 write requests per second.
PolarDB for PostgreSQL 18 includes enterprise features not available in standard PostgreSQL, such as Transparent Data Encryption (TDE), Global Plan Cache (GPC), and server-side GBK/GB18030 character set support. The platform ships with Ganos for geospatial workloads and pgvector for AI-powered vector search. Storage scales automatically up to 500 TB without manual provisioning, and snapshot-based backups complete in minutes regardless of database size.
PolarDB applies kernel-level optimizations including profile-guided optimization (PGO), BOLT binary optimization, and link-time optimization (LTO) to improve execution efficiency. Physical replication replaces binlog-based logical replication, ensuring heavy DDL operations like index additions don’t cause replication delays. The service maintains 100% compatibility with native PostgreSQL across versions 11, 14, 15, 16, 17, and now 18.
What’s Next for PostgreSQL 18 on PolarDB
PostgreSQL 18 is currently available in PolarDB through a whitelist approval process that requires submitting a support ticket. Alibaba Cloud recommends against using the current version in production environments due to potential stability issues identified during PostgreSQL 18.0 testing. The company contributed multiple bug reports and fixes back to the PostgreSQL community during the integration process.
General availability is expected after PostgreSQL 18.1 is released, which will address remaining stability concerns. PolarDB plans to migrate additional enterprise features from earlier versions to PostgreSQL 18, including serverless architecture, hot-and-cold tiered storage, and distributed deployments. Data checksums are enabled by default in new PostgreSQL 18 clusters, providing stronger data integrity validation.
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What is PostgreSQL 18 and when was it released?
PostgreSQL 18 is the latest major version of the open-source relational database, released September 25, 2025, by the PostgreSQL Global Development Group. It introduces asynchronous I/O, skip scan indexing, native UUIDv7 support, and virtual generated columns.
Is PostgreSQL 18 available on Alibaba Cloud PolarDB?
Yes, PolarDB for PostgreSQL 18 is available now through a whitelist approval process that requires submitting a support ticket. General availability without whitelist restrictions will begin after PostgreSQL 18.1 is released for production-ready stability.
What are the main performance improvements in PostgreSQL 18?
The asynchronous I/O subsystem speeds up sequential scans and VACUUM operations by up to 3× in early tests. Skip scan indexing improves queries on multi-column indexes, and parallel GIN index creation accelerates full-text and JSON workloads.
How does PolarDB differ from standard PostgreSQL?
PolarDB uses compute-storage separation architecture with shared distributed storage, enabling 5-minute scaling and supporting up to 15 read replicas. It adds enterprise features like Transparent Data Encryption, Global Plan Cache, and automatic storage scaling to 500 TB.
