code: @Override
    public boolean upgrade() {
      int schemaVersion = versionService.getSchemaVersion();
      if (schemaVersion < 31) {
        throw new UnsupportedOperationException(
            "Upgrading from schema version below 31 is not supported");
      }
      if (schemaVersion < versionService.getAppVersion()) {
        LOG.info(
            "Metadata version:{}, current version:{} upgrade needed",
            schemaVersion,
            versionService.getAppVersion());
  
        upgrades
            .stream()
            .filter(upgrade -> upgrade.getFromVersion() >= schemaVersion)
            .forEach(this::runUpgrade);
  
        versionService.setSchemaVersion(versionService.getAppVersion());
  
        LOG.info("Metadata upgrade done.");
        return true;
      } else {
        LOG.debug(
            "Metadata version:{}, current version:{} upgrade not needed",
            schemaVersion,
            versionService.getAppVersion());
        return false;
      }
    }
docs: Executes MOLGENIS MetaData version upgrades.
  
  @return true if an upgrade was necessary, false if not