PostgreSQL Linux packages, versions, and PGDG

“Install PostgreSQL on Linux” is not one stable command. The distribution, release, repository source, CPU architecture, and package name jointly determine the installed major, packaging revision, and security fixes. This page combines changing package evidence from PkgSeek with this guide's installation and upgrade rules.

Distinguish four package families

Similar names do not prove identical roles. Verify the client and server separately after installation:

psql --version
sudo -u postgres psql -X -d postgres \
  -c "select version(), current_setting('server_version_num');"

Distribution repositories and PGDG

Distribution repositories generally maintain a selected major. The PostgreSQL Global Development Group repositories are commonly used for other supported majors. Adding PGDG creates an external software-source dependency, so record repository signing, release support, upgrade policy, and an exit path.

The tables query exact coordinates in the Ubuntu and PGDG repositories separately. If a card reports “no exact indexed coordinate”, that describes index coverage, not the target repository's contents. Use the target system's apt-cache policy and official PostgreSQL repository instructions as the final installation evidence.

apt-cache policy postgresql postgresql-18 postgresql-client-18
apt-cache madison postgresql-18

Track PostgreSQL 19 packages

A missing stable distribution package is expected while PostgreSQL 19 remains in beta. Even after a test build appears, keep the beta compatibility lane separate from production PostgreSQL 18. Use the PostgreSQL 18-to-19 upgrade guide for adoption criteria.

Use package evidence safely

1. Record distro + release + source + repository + architecture + full version.
2. Determine whether a package contains the server, client, development files, or an extension.
3. For CVEs, prioritize distribution advisories and backport status over an upstream version prefix.
4. After installation, verify the connected server; psql --version only identifies the client.
5. A major change requires pg_upgrade, dump/restore, or logical replication. Replacing a package does not upgrade a data directory.

Minimum contract for an AI agent

task: resolve_postgresql_package
target:
  distro: ubuntu
  release: noble
  architecture: amd64
  source: pgdg
requirements:
  - return exact package coordinates and observed_at
  - separate indexed fact, inference, and unknown
  - never interpret missing index data as package absence
  - ask before repository, package, service, or data changes
  - verify client and server versions after execution

PkgSeek publishes a read-only MCP tool catalogue and an OpenAPI 3.1 specification. See the AI context contract for the execution boundary.