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This article will explain in detail what are the strange events about mysql slow query. The editor thinks it is very practical, so I share it with you for reference. I hope you can get something after reading this article.

Open the mysql slow query log and find that many sql queries take a very short time. Obviously, sql of less than 0.01s is also included in the slow log query. The log details are as follows:

# User@Host: otterpro [otterpro] @ [172.22.53.122] Id: 2061

# Schema: otter Last_errno: 0 Killed: 0

# Query_time: 0.000559 Lock_time: 0.000080 Rows_sent: 3 Rows_examined: 327 Rows_affected: 0

# Bytes_sent: 755

SET timestamp=1512715920

Select ID,NODE_ID,PIPELINE_ID,LOCATION,GMT_CREATE,GMT_MODIFIED from PIPELINE_NODE_RELATION where NODE_ID = 74 ORDER BY ID DESC

# Time: 171208 14:52:08

# User@Host: otterpro [otterpro] @ [172.22.53.122] Id: 2061

# Schema: otter Last_errno: 0 Killed: 0

# Query_time: 0.000214 Lock_time: 0.000110 Rows_sent: 2 Rows_examined: 2 Rows_affected: 0

# Bytes_sent: 821

SET timestamp=1512715928

Select ID,CLUSTER_NAME,SERVER_LIST,DESCRIPTION,GMT_CREATE,GMT_MODIFIED from AUTOKEEPER_CLUSTER ORDER BY ID ASC

A little skeptical. Check the parameters again:

Mysql > show global status like'% slow_queries%'

+-+ +

| | Variable_name | Value |

+-+ +

| | Slow_queries | 6055683 | |

+-+ +

Mysql > show variables like'% slow_query_log%'

+-+

| | Variable_name | Value |

+-+

| | slow_query_log | ON |

| | slow_query_log_always_write_time | 10.000000 | |

| | slow_query_log_file | / data/mysql/13306/tmp/slow.log |

| | slow_query_log_timestamp_always | OFF |

| | slow_query_log_timestamp_precision | second |

| | slow_query_log_use_global_control |

+-+

6 rows in set (0.01 sec)

Mysql > show variables like 'long_query_time'

+-+ +

| | Variable_name | Value |

+-+ +

| | long_query_time | 0.100000 | |

+-+ +

1 row in set (0.00 sec)

Mysql > show global variables like'% general%'

+-- +

| | Variable_name | Value |

+-- +

| | general_log | OFF |

| | general_log_file | / data/mysql/13306/tmp/file.sql |

+-- +

2 rows in set (0.00 sec)

Log-queries-not-using-indexes

If you run a SQL statement that does not use an index, the mysql database also logs the SQL statement to the slow query log file.

This is the end of this article on "what are the strange events of mysql slow query". I hope the above content can be of some help to you, so that you can learn more knowledge. if you think the article is good, please share it for more people to see.

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