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是否有解釋這些狀態的地方？mysql profiler「發送數據」
http://dev.mysql.com/tech-resources/articles/using-new-query-profiler.html
我的具體問題是關於這個查詢：
select count(*)
from 135_5m.record_updates u, 135_5m.records r
where r.record_id = u.record_id and
(u.date_updated > null or null is null) and
u.date_updated <= '2011-01-03';
它返回一個數字 - 4053904.那麼，爲什麼大多數的時間花費在「發送數據」？它只是名字不好嗎？當然，「發送數據」不僅僅是發送數據？
+--------------------------------+-----------+-------+
| Status | Duration | Swaps |
+--------------------------------+-----------+-------+
| starting | 0.000224 | 0 |
| checking query cache for query | 0.000188 | 0 |
| checking permissions | 0.000012 | 0 |
| checking permissions | 0.000017 | 0 |
| Opening tables | 0.000036 | 0 |
| System lock | 0.000015 | 0 |
| Table lock | 0.000067 | 0 |
| init | 0.000105 | 0 |
| optimizing | 0.000052 | 0 |
| statistics | 0.000254 | 0 |
| preparing | 0.000061 | 0 |
| executing | 0.000017 | 0 |
| Sending data | 32.079549 | 0 |
| end | 0.000036 | 0 |
| query end | 0.000012 | 0 |
| freeing items | 0.000089 | 0 |
| storing result in query cache | 0.000022 | 0 |
| logging slow query | 0.000008 | 0 |
| logging slow query | 0.000008 | 0 |
| cleaning up | 0.000011 | 0 |
+--------------------------------+-----------+-------+
題外話，但什麼是該位的目的的majrity時間'u.date_updated>空或null爲null'？肯定它總是真的？ – 2010-09-07 13:00:17
該查詢最初是java代碼中的預備狀態。我取代了？在我的代碼中使用實際值來測試性能。 – andersonbd1 2010-09-07 14:33:21