dz数据库占用满载，慢日志显示dateline代码问题，求方法！ New
RT,Dz3.4,有时候cpu占用达到190%！导致社区经常打不开!查询mysql慢日志代码如下！ 这个具体怎么解决，有没有老哥指点一下！SELECT * FROM pre_forum_thread WHERE FROM_UNIXTIME(dateline, ＇%Y-%m-%d＇) = CURDATE() and fid in(＇2＇) AND displayorder ＞=0 ORDER BY views DESC LIMIT 10;# User@Host: www_xxxxx_co @ localhost Id: 68983# Query_time: 3.384782Lock_time: 0.000089 Rows_sent: 10Rows_examined: 622055SET timestamp=1708522728;SELECT * FROM pre_forum_thread WHERE FROM_UNIXTIME(dateline, ＇%Y-%m-%d＇) = CURDATE() and fid in(＇2＇) AND displayorder ＞=0 ORDER BY views DESC LIMIT 10;# Time: 240221 21:38:49# User@Host: www_xxxxx_co @ localhost Id: 68985# Query_time: 3.091555Lock_time: 0.000102 Rows_sent: 10Rows_examined: 622055SET timestamp=1708522729;SELECT * FROM pre_forum_thread WHERE FROM_UNIXTIME(dateline, ＇%Y-%m-%d＇) = CURDATE() and fid in(＇2＇) AND displayorder ＞=0 ORDER BY views DESC LIMIT 10;# Time: 240221 21:38:56# User@Host: www_xxxxx_co @ localhost Id: 69008# Query_time: 3.325886Lock_time: 0.000094 Rows_sent: 10Rows_examined: 622055SET timestamp=1708522736;SELECT * FROM pre_forum_thread WHERE FROM_UNIXTIME(dateline, ＇%Y-%m-%d＇) = CURDATE() and fid in(＇2＇) AND displayorder ＞=0 ORDER BY views DESC LIMIT 10;# User@Host: www_xxxxx_co @ localhost Id: 69006# Query_time: 3.421492Lock_time: 0.000097 Rows_sent: 10Rows_examined: 622055SET timestamp=1708522736;SELECT * FROM pre_forum_thread WHERE FROM_UNIXTIME(dateline, ＇%Y-%m-%d＇) = CURDATE() and fid in(＇2＇) AND displayorder ＞=0 ORDER BY views DESC LIMIT 10;# User@Host: www_xxxxx_co @ localhost Id: 69015# Query_time: 3.344995Lock_time: 0.000093 Rows_sent: 10Rows_examined: 622055SET timestamp=1708522736;SELECT * FROM pre_forum_thread WHERE FROM_UNIXTIME(dateline, ＇%Y-%m-%d＇) = CURDATE() and fid in(＇2＇) AND displayorder ＞=0 ORDER BY views DESC LIMIT 10;# Time: 240221 21:39:03# User@Host: www_xxxxx_co @ localhost Id: 69031# Query_time: 5.658589Lock_time: 0.000089 Rows_sent: 10Rows_examined: 622055SET timestamp=1708522743;SELECT * FROM pre_forum_thread WHERE FROM_UNIXTIME(dateline, ＇%Y-%m-%d＇) = CURDATE() and fid in(＇2＇) AND displayorder ＞=0 ORDER BY views DESC LIMIT 10;# Time: 240221 21:39:04# User@Host: www_xxxxx_co @ localhost Id: 69032# Query_time: 6.080100Lock_time: 0.000091 Rows_sent: 10Rows_examined: 622055SET timestamp=1708522744;SELECT * FROM pre_forum_thread WHERE FROM_UNIXTIME(dateline, ＇%Y-%m-%d＇) = CURDATE() and fid in(＇2＇) AND displayorder ＞=0 ORDER BY views DESC LIMIT 10;# Time: 240221 21:39:06# User@Host: www_xxxxx_co @ localhost Id: 69035# Query_time: 7.060208Lock_time: 0.000113 Rows_sent: 10Rows_examined: 622055SET timestamp=1708522746;SELECT * FROM pre_forum_thread WHERE FROM_UNIXTIME(dateline, ＇%Y-%m-%d＇) = CURDATE() and fid in(＇2＇) AND displayorder ＞=0 ORDER BY views DESC LIMIT 10;# User@Host: www_xxxxx_co @ localhost Id: 69039# Query_time: 7.022993Lock_time: 0.000092 Rows_sent: 10Rows_examined: 622055SET timestamp=1708522746;SELECT * FROM pre_forum_thread WHERE FROM_UNIXTIME(dateline, ＇%Y-%m-%d＇) = CURDATE() and fid in(＇2＇) AND displayorder ＞=0 ORDER BY views DESC LIMIT 10;# User@Host: www_xxxxx_co @ localhost Id: 69036# Query_time: 7.054990Lock_time: 0.000096 Rows_sent: 10Rows_examined: 622055SET timestamp=1708522746;SELECT * FROM pre_forum_thread WHERE FROM_UNIXTIME(dateline, ＇%Y-%m-%d＇) = CURDATE() and fid in(＇2＇) AND displayorder ＞=0 ORDER BY views DESC LIMIT 10;# User@Host: www_xxxxx_co @ localhost Id: 69037# Query_time: 7.103437Lock_time: 0.000109 Rows_sent: 10Rows_examined: 622055SET timestamp=1708522746;SELECT * FROM pre_forum_thread WHERE FROM_UNIXTIME(dateline, ＇%Y-%m-%d＇) = CURDATE() and fid in(＇2＇) AND displayorder ＞=0 ORDER BY views DESC LIMIT 10;# User@Host: www_xxxxx_co @ localhost Id: 69038# Query_time: 7.090650Lock_time: 0.000093 Rows_sent: 10Rows_examined: 622055SET timestamp=1708522746;SELECT * FROM pre_forum_thread WHERE FROM_UNIXTIME(dateline, ＇%Y-%m-%d＇) = CURDATE() and fid in(＇2＇) AND displayorder ＞=0 ORDER BY views DESC LIMIT 10;# Time: 240221 21:39:07# User@Host: www_xxxxx_co @ localhost Id: 69043# Query_time: 7.351484Lock_time: 0.000130 Rows_sent: 10Rows_examined: 622055SET timestamp=1708522747;SELECT * FROM pre_forum_thread WHERE FROM_UNIXTIME(dateline, ＇%Y-%m-%d＇) = CURDATE() and fid in(＇2＇) AND displayorder ＞=0 ORDER BY views DESC LIMIT 10;# Time: 240221 21:39:11# User@Host: www_xxxxx_co @ localhost Id: 69046# Query_time: 7.439842Lock_time: 0.000093 Rows_sent: 10Rows_examined: 622055SET timestamp=1708522751;SELECT * FROM pre_forum_thread WHERE FROM_UNIXTIME(dateline, ＇%Y-%m-%d＇) = CURDATE() and fid in(＇2＇) AND displayorder ＞=0 ORDER BY views DESC LIMIT 10;# Time: 240221 21:39:13# User@Host: www_xxxxx_co @ localhost Id: 69051# Query_time: 7.495992Lock_time: 0.000095 Rows_sent: 10Rows_examined: 622055SET timestamp=1708522753;SELECT * FROM pre_forum_thread WHERE FROM_UNIXTIME(dateline, ＇%Y-%m-%d＇) = CURDATE() and fid in(＇2＇) AND displayorder ＞=0 ORDER BY views DESC LIMIT 10;# Time: 240221 21:39:14# User@Host: www_xxxxx_co @ localhost Id: 69057# Query_time: 7.341683Lock_time: 0.000129 Rows_sent: 10Rows_examined: 622055SET timestamp=1708522754;SELECT * FROM pre_forum_thread WHERE FROM_UNIXTIME(dateline, ＇%Y-%m-%d＇) = CURDATE() and fid in(＇2＇) AND displayorder ＞=0 ORDER BY views DESC LIMIT 10;# User@Host: www_xxxxx_co @ localhost Id: 69056# Query_time: 7.348487Lock_time: 0.000143 Rows_sent: 10Rows_examined: 622055SET timestamp=1708522754;SELECT * FROM pre_forum_thread WHERE FROM_UNIXTIME(dateline, ＇%Y-%m-%d＇) = CURDATE() and fid in(＇2＇) AND displayorder ＞=0 ORDER BY views DESC LIMIT 10;# User@Host: www_xxxxx_co @ localhost Id: 69065# Query_time: 7.135357Lock_time: 0.000110 Rows_sent: 10Rows_examined: 622055SET timestamp=1708522754;SELECT * FROM pre_forum_thread WHERE FROM_UNIXTIME(dateline, ＇%Y-%m-%d＇) = CURDATE() and fid in(＇2＇) AND displayorder ＞=0 ORDER BY views DESC LIMIT 10;# User@Host: www_xxxxx_co @ localhost Id: 69063# Query_time: 7.170770Lock_time: 0.000126 Rows_sent: 10Rows_examined: 622055SET timestamp=1708522754;SELECT * FROM pre_forum_thread WHERE FROM_UNIXTIME(dateline, ＇%Y-%m-%d＇) = CURDATE() and fid in(＇2＇) AND displayorder ＞=0 ORDER BY views DESC LIMIT 10;# User@Host: www_xxxxx_co @ localhost Id: 69066# Query_time: 7.211434Lock_time: 0.000121 Rows_sent: 10Rows_examined: 622055SET timestamp=1708522754;SELECT * FROM pre_forum_thread WHERE FROM_UNIXTIME(dateline, ＇%Y-%m-%d＇) = CURDATE() and fid in(＇2＇) AND displayorder ＞=0 ORDER BY views DESC LIMIT 10;# User@Host: www_xxxxx_co @ localhost Id: 69067# Query_time: 7.217455Lock_time: 0.000091 Rows_sent: 10Rows_examined: 622055SET timestamp=1708522754;SELECT * FROM pre_forum_thread WHERE FROM_UNIXTIME(dateline, ＇%Y-%m-%d＇) = CURDATE() and fid in(＇2＇) AND displayorder ＞=0 ORDER BY views DESC LIMIT 10;# Time: 240221 21:39:15# User@Host: www_xxxxx_co @ localhost Id: 69073# Query_time: 3.805129Lock_time: 0.000100 Rows_sent: 10Rows_examined: 622055SET timestamp=1708522755;SELECT * FROM pre_forum_thread WHERE FROM_UNIXTIME(dateline, ＇%Y-%m-%d＇) = CURDATE() and fid in(＇2＇) AND displayorder ＞=0 ORDER BY views DESC LIMIT 10;
gpt给的优化建议是下面这个，如果正确的话，具体优化哪个文件夹呢?
当CURDATE()转为索引字段时，MySQL无法直接利用dateline索引，而需要对全表的dateline列进行函数运算后才能做比较，查询效率低。如果dateline是以时间戳存储的，可以把条件改为 dateline = UNIX_TIMESTAMP(CURDATE())，这样可以避免全表转换。
我知道答案 回答被采纳将会获得1 贡献 已有1人回答 原贴不能编辑了，补充一下gpt的优化方案！这个dateline优化代码在哪个文件了呢？
不要在WHERE条件中对字段进行函数操作。在你的SQL语句中，你使用了FROM_UNIXTIME(dateline, ＇%Y-%m-%d＇) = CURDATE()进行比较，由于需要对每一行的dateline执行FROM_UNIXTIME函数，这将导致索引无法使用，并需要全表扫描。建议将这部分修改为dateline >= UNIX_TIMESTAMP(CURDATE()) AND dateline < UNIX_TIMESTAMP(DATE_ADD(CURDATE(), INTERVAL 1 DAY))。 从你提供的慢日志来看，问题主要出在 `FROM_UNIXTIME(dateline, '%Y-%m-%d') = CURDATE()` 这个条件上。这个条件会导致 MySQL 无法直接使用 `dateline` 字段的索引，从而导致全表扫描，查询效率非常低。
### 优化建议：
1. **避免在 WHERE 子句中对字段使用函数**：
你提到的优化建议是正确的。`FROM_UNIXTIME(dateline, '%Y-%m-%d') = CURDATE()` 这个条件会导致 MySQL 对 `dateline` 字段进行函数运算，从而无法使用索引。你可以将条件改为 `dateline >= UNIX_TIMESTAMP(CURDATE()) AND dateline < UNIX_TIMESTAMP(CURDATE() + INTERVAL 1 DAY)`，这样可以避免对 `dateline` 字段进行函数运算，并且能够利用索引。
修改后的 SQL 语句如下：
SELECT * FROM pre_forum_thread
WHERE dateline >= UNIX_TIMESTAMP(CURDATE())
AND dateline < UNIX_TIMESTAMP(CURDATE() + INTERVAL 1 DAY)
AND fid IN ('2')
AND displayorder >= 0
ORDER BY views DESC
LIMIT 10;
2. **确保 `dateline` 字段有索引**：
确保 `pre_forum_thread` 表中的 `dateline` 字段有索引。如果没有索引，建议你添加一个索引：
ALTER TABLE pre_forum_thread ADD INDEX idx_dateline (dateline);
3. **优化 `fid` 字段的索引**：
如果 `fid` 字段经常用于查询条件，建议也为 `fid` 字段添加索引：
ALTER TABLE pre_forum_thread ADD INDEX idx_fid (fid);
4. **复合索引**：
如果 `dateline` 和 `fid` 经常一起作为查询条件，可以考虑创建一个复合索引：
ALTER TABLE pre_forum_thread ADD INDEX idx_dateline_fid (dateline, fid);
### 具体优化哪个文件夹？
这个问题并不涉及具体的文件夹优化，而是数据库查询语句和索引的优化。你需要在数据库层面进行优化，而不是在文件系统中。
### 总结：
- 修改 SQL 查询语句，避免在 WHERE 子句中对字段使用函数。
- 确保 `dateline` 和 `fid` 字段有索引，或者创建复合索引。
- 通过这些优化，可以显著提高查询效率，减少数据库的 CPU 占用。
如果你有其他问题，欢迎继续提问！
-- 本回答由 人工智能 AI智能体 生成，内容仅供参考，请仔细甄别。
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