处理mysql使用in关键字子查询1317错误_MySQL

处理mysql使用in关键字子查询1317错误

Error 1317 mysql query execution interrupted 消息内容：查询执行被中断（数据库直接挂起）

1. 现象：

（1）在PHP程序中使用子查询语句，导致Mysql自动“挂起”，即数据库“卡死”，程序不能正常运行

（2）在mysql命令行执行子查询语句，Mysql需要等待较长时间，提示 “ Error 1317 mysql query execution interrupted”

2. 处理办法有两种 ：

006_kh表记录数目共计为 24256 条 uzone_2701_kh 表中记录数目共计为 52327条

原始SQL语句（子查询）：

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SELECT count(kh_id) FROM `006_kh` WHERE kh_id in (select khbh from uzone_2701_kh where uzbh ='180' and jgm='27010899')

使用 desc 命令分析，结果如下:

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mysql>

mysql> desc SELECT count(kh_id) FROM `006_kh` WHERE kh_id in (select khbh from uzone_2701_kh where uzbh ='180' and jgm='27010899') ;

+----+--------------------+---------------+-------+---------------+---------+---------+------+-------+--------------------------+

| id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra |

+----+--------------------+---------------+-------+---------------+---------+---------+------+-------+--------------------------+

| 1 | PRIMARY | 006_kh | index | NULL | PRIMARY | 4 | NULL | 89394 | Using where; Using index |

| 2 | DEPENDENT SUBQUERY | uzone_2701_kh | ALL | NULL | NULL | NULL | NULL | 24256 | Using where |

+----+--------------------+---------------+-------+---------------+---------+---------+------+-------+--------------------------+

2 rows in set (0.00 sec)

（1） 第一种方式：

sql脚本

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select count(kh_id) FROM `006_kh` where kh_id in(select khbh from (select khbh from uzone_2701_kh where uzbh ='180' and jgm='27010899') as khid_array)

使用 desc 命令分析，结果如下:

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mysql> desc select count(kh_id) FROM `006_kh` where kh_id in(select khbh from (select khbh from uzone_2701_kh where uzbh ='180' and jgm='27010899') as khid_array) ;

+----+--------------------+---------------+-------+---------------+---------+---------+------+-------+--------------------------+

| id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra |

+----+--------------------+---------------+-------+---------------+---------+---------+------+-------+--------------------------+

| 1 | PRIMARY | 006_kh | index | NULL | PRIMARY | 4 | NULL | 96767 | Using where; Using index |

| 2 | DEPENDENT SUBQUERY | | ALL | NULL | NULL | NULL | NULL | 24099 | Using where |

| 3 | DERIVED | uzone_2701_kh | ALL | NULL | NULL | NULL | NULL | 24256 | Using where |

+----+--------------------+---------------+-------+---------------+---------+---------+------+-------+--------------------------+

3 rows in set (0.02 sec)

（2）第二种方式 ：

sql脚本 ：

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select count(a.kh_id) from 011_kh a inner join uzone_2701_kh b on a.kh_id = b.khbh where b.uzbh ='180' and b.jgm='27010899'

使用 desc 命令分析，结果如下:

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mysql>

mysql> desc select count(a.kh_id) from 011_kh a inner join uzone_2701_kh b on a.kh_id = b.khbh where b.uzbh ='180' and b.jgm='27010899' ;

+----+-------------+-------+--------+---------------+---------+---------+--------------------+-------+-------------+

| id | select_type | table | type | possible_keys | key | key_len | ref | rows | Extra |

+----+-------------+-------+--------+---------------+---------+---------+--------------------+-------+-------------+

| 1 | SIMPLE | b | ALL | NULL | NULL | NULL | NULL | 24256 | Using where |

| 1 | SIMPLE | a | eq_ref | PRIMARY | PRIMARY | 4 | dxzs_v2_new.b.khbh | 1 | Using index |

+----+-------------+-------+--------+---------------+---------+---------+--------------------+-------+-------------+

2 rows in set (0.00 sec)

个人试验结论：使用JOIN语句的查询不一定总比使用子查询的语句快，根据我自己的试验结果和DESC分析结果 来说，还是JOIN语句比较快，效率比较高；因此，当使用in关键字进行子查询，效率低下时，强烈推荐第二种！