private static String dataTypeNullability(String type) {
        if (type.equals(ClickHouseDataType.Nullable.name()) || type.equals(ClickHouseDataType.Dynamic.name())) {
            return String.valueOf(java.sql.DatabaseMetaData.typeNullable);
        }
        return String.valueOf(java.sql.DatabaseMetaData.typeNoNulls);
    }
Returns name of the ClickHouse table types as the broad category (rather than engine name).
@return - ResultSet with one column TABLE_TYPE
@throws SQLException - if an error occurs
jdbc-v2/src/main/java/com/clickhouse/jdbc/metadata/DatabaseMetaDataImpl.java