Mongodb/completeness

| Q                   | A
| ------------------- | ---
| Bug fix?            | No
| New feature?        | Yes
| BC breaks?          | Yes
| Tests pass?         | Yes
| Scenarios pass?     | Yes
| Checkstyle issues?  | Yes
| Changelog updated?  | Yes
| Fixed tickets       | N.A.
| Doc PR              | N.A.