打得二手好软广

@saber000 谢谢

@realityone 嗯嗯，加了code和msg，输出是502

@nicai000 斜线也行，问题就是7楼说的，多了一个'#'

@Jeremial 额，还真是，去掉一个井就好了。。。
智商已经被眼睛打晕在厕所
3ks

@proudzhu 应该不能去掉，去掉之后仍然报错，附言里面的

@Jeremial 这一句原来的配置里就写了，就没有重新写

怎么判断是不是二手的？

打印了代码的T恤。。。

@xiaobaigsy 我网上查的是sending data也包括过滤数据的过程，如果是的话，那应该还是查得慢

@lhbc 网络我不懂，不过A和B不是直接连接的，B是先到公网再到C的，A到C也是先到公网再到C的。
之前我就问过网工能不能A直接访问B，他说搞不定。我不知道是我没讲明白还是他不懂。A直接连B能实现吗?
还有什么情况下要用到代理啊

@xiaobaigsy

mysql> select @@profiling;
+-------------+
| @@profiling |
+-------------+
| 0 |
+-------------+
1 row in set (0.06 sec)

mysql> set profiling=1;
Query OK, 0 rows affected (0.01 sec)

mysql> select count(1) from history_uint;
+----------+
| count(1) |
+----------+
| 3464122 |
+----------+
1 row in set (1 min 52.51 sec)

mysql> show profiles;
+----------+--------------+-----------------------------------+
| Query_ID | Duration | Query |
+----------+--------------+-----------------------------------+
| 1 | 20.63920150 | select count(*) from history_uint |
| 2 | 112.46709225 | select count(1) from history_uint |
+----------+--------------+-----------------------------------+
2 rows in set (0.06 sec)

mysql> show profile for query 2;
+----------------------+------------+
| Status | Duration |
+----------------------+------------+
| starting | 0.000042 |
| checking permissions | 0.000007 |
| Opening tables | 0.000017 |
| System lock | 0.000009 |
| init | 0.000010 |
| optimizing | 0.000008 |
| statistics | 0.000011 |
| preparing | 0.000008 |
| executing | 0.000004 |
| Sending data | 112.466869 |
| end | 0.000019 |
| query end | 0.000006 |
| closing tables | 0.000014 |
| freeing items | 0.000058 |
| logging slow query | 0.000004 |
| logging slow query | 0.000003 |
| cleaning up | 0.000005 |
+----------------------+------------+
17 rows in set (0.03 sec)

mysql> show profile block io,cpu for query 2;
+----------------------+------------+-----------+------------+--------------+---
------------+
| Status | Duration | CPU_user | CPU_system | Block_ops_in | Bl
ock_ops_out |
+----------------------+------------+-----------+------------+--------------+---
------------+
| starting | 0.000042 | 0.000000 | 0.000000 | NULL |
NULL |
| checking permissions | 0.000007 | 0.000000 | 0.000000 | NULL |
NULL |
| Opening tables | 0.000017 | 0.000000 | 0.000000 | NULL |
NULL |
| System lock | 0.000009 | 0.000000 | 0.000000 | NULL |
NULL |
| init | 0.000010 | 0.000000 | 0.000000 | NULL |
NULL |
| optimizing | 0.000008 | 0.000000 | 0.000000 | NULL |
NULL |
| statistics | 0.000011 | 0.000000 | 0.000000 | NULL |
NULL |
| preparing | 0.000008 | 0.000000 | 0.000000 | NULL |
NULL |
| executing | 0.000004 | 0.000000 | 0.000000 | NULL |
NULL |
| Sending data | 112.466869 | 27.331375 | 3.759624 | NULL |
NULL |
| end | 0.000019 | 0.000000 | 0.000000 | NULL |
NULL |
| query end | 0.000006 | 0.000000 | 0.000000 | NULL |
NULL |
| closing tables | 0.000014 | 0.000000 | 0.000000 | NULL |
NULL |
| freeing items | 0.000058 | 0.000000 | 0.000000 | NULL |
NULL |
| logging slow query | 0.000004 | 0.000000 | 0.000000 | NULL |
NULL |
| logging slow query | 0.000003 | 0.000000 | 0.000000 | NULL |
NULL |
| cleaning up | 0.000005 | 0.000000 | 0.000000 | NULL |
NULL |
+----------------------+------------+-----------+------------+--------------+---
------------+
17 rows in set (0.04 sec)

@heyli | history_uint | CREATE TABLE `history_uint` (
`itemid` bigint(20) unsigned NOT NULL,
`clock` int(11) NOT NULL DEFAULT '0',
`value` bigint(20) unsigned NOT NULL DEFAULT '0',
`ns` int(11) NOT NULL DEFAULT '0',
KEY `history_uint_1` (`itemid`,`clock`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE=utf8_bin |

是InnoDB的
所以逐行扫描会这么慢？但是30万行的时候还是挺快的啊，多了一个数量级，差的时间可不只是差一个数量级啊，而且慢得恐怖啊

@wanjun 是没有主键，是跟这有关系吗

@heyli mysql默认不是myisam吗,没改过

@tb4649120073rs mysql> explain select count(*) from history_uint;
+----+-------------+--------------+-------+---------------+----------------+----
-----+------+---------+-------------+
| id | select_type | table | type | possible_keys | key | key
_len | ref | rows | Extra |
+----+-------------+--------------+-------+---------------+----------------+----
-----+------+---------+-------------+
| 1 | SIMPLE | history_uint | index | NULL | history_uint_1 | 12
| NULL | 3393731 | Using index |
+----+-------------+--------------+-------+---------------+----------------+----
-----+------+---------+-------------+
1 row in set (0.00 sec)

@tb4649120073rs
mysql> explain history_uint;
+--------+---------------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+--------+---------------------+------+-----+---------+-------+
| itemid | bigint(20) unsigned | NO | MUL | NULL | |
| clock | int(11) | NO | | 0 | |
| value | bigint(20) unsigned | NO | | 0 | |
| ns | int(11) | NO | | 0 | |
+--------+---------------------+------+-----+---------+-------+
4 rows in set (0.09 sec)

@fising 对数据库不懂，而且现在只允许查询，不允许对表结构和内容作修改.我只是觉得这查询速度不太正常，想确认一下是不是不正常和什么原因