diff --git a/doc/install/postgresql_extensions.md b/doc/install/postgresql_extensions.md
index 8d5a2a79b72aaab13a723b646b8bf8cecd43df94..663ec547733eaa1e78db9990de79ec0ca29b8495 100644
--- a/doc/install/postgresql_extensions.md
+++ b/doc/install/postgresql_extensions.md
@@ -15,6 +15,7 @@ The following extensions must be loaded into the GitLab database:
 |--------------|------------------------|
 | `pg_trgm`    | 8.6                    |
 | `btree_gist` | 13.1                   |
+| `plpgsql`    | 11.7                   |
 
 In order to install extensions, PostgreSQL requires the user to have superuser privileges.
 Typically, the GitLab database user is not a superuser. Therefore, regular database migrations