OceanBase 的 SQL 引擎支持执行计划解析和缓存技术，可以通过分析查询语句的执行计划来分析查询性能。执行计划查看的语法格式如下：

    1. explain [extended] query_statment ;

    示例：查看查询执行计划

    1. obclient> EXPLAIN select  count(*) from stok \G
    2. *************************** 1. row ***************************
    3. Query Plan: ========================================================
    4. |ID|OPERATOR                 |NAME    |EST. ROWS|COST  |
    5. --------------------------------------------------------
    6. |0 |SCALAR GROUP BY          |        |1        |600337|
    7. |1 | PX COORDINATOR          |        |1        |485729|
    8. |2 |  EXCHANGE OUT DISTR     |:EX10000|1        |485729|
    9. |3 |   MERGE GROUP BY        |        |1        |485729|
    10. |4 |    PX PARTITION ITERATOR|        |600000   |371122|
    11. |5 |     TABLE SCAN          |stok    |600000   |371122|
    12. ========================================================
    14. Outputs & filters:
    15. -------------------------------------
    16.   0 - output([T_FUN_COUNT_SUM(T_FUN_COUNT(*))]), filter(nil),
    17.       group(nil), agg_func([T_FUN_COUNT_SUM(T_FUN_COUNT(*))])
    18.   1 - output([T_FUN_COUNT(*)]), filter(nil)
    19.   2 - output([T_FUN_COUNT(*)]), filter(nil), dop=1
    20.   3 - output([T_FUN_COUNT(*)]), filter(nil),
    21.       group(nil), agg_func([T_FUN_COUNT(*)])
    22.   4 - output([stok.s_i_id]), filter(nil)
    23.   5 - output([stok.s_i_id]), filter(nil),
    24.       access([stok.s_i_id]), partitions(p[0-5])