將profiling的結果有序排列顯示

首先開啓profiling

set profiling=1；

root@localhost>select * from  nicer_but_slower_film_list;
root@localhost>show profiles;
+----------+------------+-------------------------------------------+
| Query_ID | Duration   | Query                                     |
+----------+------------+-------------------------------------------+
|        1 | 0.00029875 | show warnings                             |
|        2 | 0.00135925 | show variables like '%profi%'             |
|        3 | 0.19135775 | select * from  nicer_but_slower_film_list |
+----------+------------+-------------------------------------------+

對剛纔的查詢語句進行性能分析

root@localhost>show profile for query 3;
+----------------------+----------+
| Status               | Duration |
+----------------------+----------+
| starting             | 0.000069 |
| checking permissions | 0.000016 |
| Opening tables       | 0.000384 |
| checking permissions | 0.000063 |
| checking permissions | 0.000015 |
| checking permissions | 0.000012 |
| checking permissions | 0.000011 |
| checking permissions | 0.000116 |
| init                 | 0.000033 |
| System lock          | 0.000057 |
| optimizing           | 0.000013 |
| optimizing           | 0.000415 |
| statistics           | 0.023471 |
| preparing            | 0.000168 |
| Creating tmp table   | 0.000301 |
| Sorting result       | 0.000021 |
| statistics           | 0.000019 |
| preparing            | 0.000018 |
| executing            | 0.000622 |
| Sending data         | 0.000089 |
| executing            | 0.000013 |
| Sending data         | 0.074418 |
| Creating sort index  | 0.080036 |
| removing tmp table   | 0.000624 |
| Creating sort index  | 0.009102 |
| end                  | 0.000016 |
| query end            | 0.000013 |
| closing tables       | 0.000008 |
| removing tmp table   | 0.000296 |
| closing tables       | 0.000027 |
| freeing items        | 0.000062 |
| removing tmp table   | 0.000011 |
| freeing items        | 0.000794 |
| cleaning up          | 0.000031 |
+----------------------+----------+
34 rows in set, 1 warning (0.00 sec)

結果是無序的，不容易閱讀。而且show profiling不支持order by排序，經過查看information_schema方案能夠獲取有序結果。

root@localhost>set @query_id=3;
Query OK, 0 rows affected (0.00 sec)

root@localhost>select state,sum(duration) as total_R,
    -> round(
    -> 100*sum(duration)/
    -> (select sum(duration) from information_schema.profiling where query_id=@query_id
    -> ),2) as pct_R,
    -> count(*) as Calls,
    -> sum(duration)/count(*) as "R/Call"
    -> from information_schema.profiling
    -> where query_id=@query_id
    -> group by state
    -> order by total_R desc;
+----------------------+----------+-------+-------+--------------+
| state                | total_R  | pct_R | Calls | R/Call       |
+----------------------+----------+-------+-------+--------------+
| Creating sort index  | 0.089138 | 46.58 |     2 | 0.0445690000 |
| Sending data         | 0.074507 | 38.93 |     2 | 0.0372535000 |
| statistics           | 0.023490 | 12.28 |     2 | 0.0117450000 |
| removing tmp table   | 0.000931 |  0.49 |     3 | 0.0003103333 |
| freeing items        | 0.000856 |  0.45 |     2 | 0.0004280000 |
| executing            | 0.000635 |  0.33 |     2 | 0.0003175000 |
| optimizing           | 0.000428 |  0.22 |     2 | 0.0002140000 |
| Opening tables       | 0.000384 |  0.20 |     1 | 0.0003840000 |
| Creating tmp table   | 0.000301 |  0.16 |     1 | 0.0003010000 |
| checking permissions | 0.000233 |  0.12 |     6 | 0.0000388333 |
| preparing            | 0.000186 |  0.10 |     2 | 0.0000930000 |
| starting             | 0.000069 |  0.04 |     1 | 0.0000690000 |
| System lock          | 0.000057 |  0.03 |     1 | 0.0000570000 |
| closing tables       | 0.000035 |  0.02 |     2 | 0.0000175000 |
| init                 | 0.000033 |  0.02 |     1 | 0.0000330000 |
| cleaning up          | 0.000031 |  0.02 |     1 | 0.0000310000 |
| Sorting result       | 0.000021 |  0.01 |     1 | 0.0000210000 |
| end                  | 0.000016 |  0.01 |     1 | 0.0000160000 |
| query end            | 0.000013 |  0.01 |     1 | 0.0000130000 |
+----------------------+----------+-------+-------+--------------+
19 rows in set (0.01 sec)