How to Fix the pgvector "could not open extension control file" Error?

In Vultr Managed Databases for PostgreSQL, you may encounter the following error when attempting to enable the pgvector extension:

ERROR: could not open extension control file "/usr/pgsql-16/share/extension/pgvector.control": No such file or directory

This typically happens when the extension name in your CREATE EXTENSION command does not match the actual identifier recognized by PostgreSQL. Although the upstream project is called pgvector, the extension is installed and registered under the name vector. As a result, PostgreSQL cannot locate a control file for pgvector because it is not registered under that name.

To correctly enable the extension, connect to your Vultr Managed Database for PostgreSQL using vultradmin and run:

defaultdb=> CREATE EXTENSION vector;

Once the extension is created, you can verify it is active by running:

defaultdb=> \dx

The output should include an entry similar to:

  Name   | Version |   Schema   |                     Description                      
---------+---------+------------+------------------------------------------------------
 vector  | 0.7.4   | public     | vector data type and ivfflat and hnsw access methods

This lists all installed extensions in the current database, including vector, which can be used for vector-based indexing and similarity search.