information_schema.partitions 视图内的 table_rows 为 NULL

*************************** 287. row ***************************
              TABLE_CATALOG: def
               TABLE_SCHEMA: university
                 TABLE_NAME: test_date_type
             PARTITION_NAME: NULL
          SUBPARTITION_NAME: NULL
 PARTITION_ORDINAL_POSITION: 0
 SUBPARTITION_ORDINAL_POSITION: 0
           PARTITION_METHOD: NULL
        SUBPARTITION_METHOD: NULL
       PARTITION_EXPRESSION: NULL
    SUBPARTITION_EXPRESSION: NULL
      PARTITION_DESCRIPTION: NULL
                 TABLE_ROWS: NULL
             AVG_ROW_LENGTH: NULL
                DATA_LENGTH: NULL
            MAX_DATA_LENGTH: NULL
               INDEX_LENGTH: NULL
                  DATA_FREE: NULL
                CREATE_TIME: NULL
                UPDATE_TIME: NULL
                 CHECK_TIME: NULL
                   CHECKSUM: NULL
          PARTITION_COMMENT: NULL
                  NODEGROUP: default
            TABLESPACE_NAME:
 287 rows in set (0.02 sec)