FAQ — PostgreSQL
Which instance presets are available?
The Instance preset sets the CPU and memory of each node of the cluster. Presets are the virtual machine sizes of the u1, s1 and m1 series: a preset has the same resources as the VM of the same name. The list displayed by the wizard is authoritative:
| Preset | CPU | Memory |
|---|---|---|
u1.medium | 1 | 4Gi |
u1.large | 2 | 8Gi |
u1.xlarge | 4 | 16Gi |
u1.2xlarge | 8 | 32Gi |
u1.4xlarge | 16 | 64Gi |
u1.8xlarge | 32 | 128Gi |
s1.small | 1 | 2Gi |
s1.medium | 2 | 4Gi |
s1.large | 4 | 8Gi |
s1.xlarge | 8 | 16Gi |
s1.2xlarge | 16 | 32Gi |
s1.4xlarge | 32 | 64Gi |
m1.large | 2 | 16Gi |
m1.xlarge | 4 | 32Gi |
m1.2xlarge | 8 | 64Gi |
m1.4xlarge | 16 | 128Gi |
m1.8xlarge | 32 | 256Gi |
The preset can be changed after creation from Edit. Defining custom CPU/memory values is not offered in the console; contact support.
How many replicas should I choose?
- 1 (Standalone): development and testing. A failure of the instance makes the database unavailable until it restarts.
- 2 (High Availability): a standby ready to take over if the primary fails.
- 3 (Max High Availability): recommended for critical production.
The number of replicas cannot be changed after creation; contact support if you need to change it.
Where can I find the connection address?
On the cluster page, in the Connection and Databases card. The Internal zone always shows the internal host; the External zone shows the public address when External Access is enabled, Disabled otherwise. The port is 5432.
How do I connect from a VM or a Kubernetes cluster in the same project without external access?
Use the host in the Internal zone, on port 5432: it is reachable from the project's VMs and Kubernetes clusters, without external access, but not from another project. Copy the full name; on a Debian 13 VM, see Reaching a managed service in the project.
I lost a user's password. How do I recover it?
Passwords are displayed only once and cannot be read again. Generate a new one: Users tab → Actions → Change Password → Perform rotation. The old password is revoked immediately.
Why is my username rejected?
PostgreSQL usernames are 3 to 16 characters long, made of lowercase letters, digits and underscores (_), and start with a letter or an underscore. The hyphen (-) is not accepted. The names postgres, admin, root, owner, superuser, streaming_replica and all those starting with pg_ are reserved.
Why is my database name rejected?
A database name is 1 to 54 characters long: lowercase letters, digits, underscores (_) and hyphens (-). It starts with a letter or an underscore, but not with pg_. The system databases postgres, template0 and template1 cannot be created.
Why is a right on the postgres database locked?
postgres, template0 and template1 are system databases, reserved for the platform: no right can be granted or changed on them anymore. The cluster creation wizard used to preselect the postgres database for users; the rights granted this way are kept. In Manage Access, such a row is shown locked, with a warning: remove it, then give the user access to an application database.
How do I add PostgreSQL extensions?
When creating a database (Databases tab → Create, PostgreSQL Extensions section) or later, via Actions → Manage extensions. The extensions offered include pg_stat_statements, pgcrypto, uuid-ossp, pg_trgm, hstore, citext, postgres_fdw, pgaudit and vector (pgvector).
Can I create several databases and users?
Yes. Add as many databases as needed in the Databases tab, and as many users as needed in the Users tab. Each user can have a different right on each database (Administrator (Admin) or Read-only).
Can I change PostgreSQL parameters (max_connections, shared_buffers…)?
These parameters are not offered in the console; contact support.
Are backups available?
Yes, from the Backups tab of the cluster page: scheduling, on-demand backup and restore, including to a point in time. See Configure backups and the backup service.