Summary of Mysql slow query operations

mysql> show variables like "%long%"; <SPAN style="COLOR: #ff00ff"> // Check the default slow query time of 10 seconds</SPAN> 
+-----------------+-----------+  
| Variable_name | Value |  
+-----------------+-----------+  
| long_query_time | 10.000000 |  
+-----------------+-----------+  
1 row in set (0.00 sec)  
  
mysql> set global long_query_time=1; <SPAN style="COLOR: #ff00ff">//Set to 1 second, add global, and it will take effect next time you enter mysql</SPAN>  
Query OK, 0 rows affected (0.00 sec)  
 
mysql> show variables like "%slow%"; <SPAN style="COLOR: #ff00ff"> // Check if slow query is enabled</SPAN> 
+---------------------+---------------------------------+  
| Variable_name | Value |  
+---------------------+---------------------------------+  
| log_slow_queries | OFF |  
| slow_launch_time | 2 |  
| slow_query_log | OFF |  
| slow_query_log_file | /usr/local/mysql/mysql-slow.log |  
+---------------------+---------------------------------+  
4 rows in set (0.00 sec)  
  
mysql> set slow_query_log='ON'; <SPAN style="COLOR: #ff00ff"> //Add global, otherwise an error will be reported</SPAN> 
ERROR 1229 (HY000): Variable 'slow_query_log' is a GLOBAL variable and should be set with SET GLOBAL 
mysql> set global slow_query_log='ON'; <SPAN style="COLOR: #ff00ff">//Setting this parameter to ON means enabling slow queries, which can capture SQL statements whose execution time exceeds a certain value. </SPAN> 
Query OK, 0 rows affected (0.28 sec)  
  
mysql> show variables like "%slow%"; <SPAN style="COLOR: #ff00ff">//Check if it is enabled</SPAN> 
+---------------------+---------------------------------+  
| Variable_name | Value |  
+---------------------+---------------------------------+  
| log_slow_queries | ON |  
| slow_launch_time | 2 |  
| slow_query_log | ON |  
| slow_query_log_file | /usr/local/mysql/mysql-slow.log |  
+---------------------+---------------------------------+  
4 rows in set (0.00 sec)

/usr/local/mysql/libexec/mysqld, Version: 5.1.26-rc-log (Source distribution). started with:  
Tcp port: 3306 Unix socket: /tmp/mysql.sock  
Time Id Command Argument  
# Time: 100814 13:28:30  
# User@Host: root[root] @ localhost []  
# Query_time: 10.096500 Lock_time: 0.045791 Rows_sent: 1 Rows_examined: 2374192  
SET timestamp=1281763710;  
select count(distinct ad_code) as x from ad_visit_history where ad_code in (select ad_code from ad_list where media_id=15);  
# Time: 100814 13:37:02  
# User@Host: root[root] @ localhost []  
# Query_time: 10.394134 Lock_time: 0.000091 Rows_sent: 1 Rows_examined: 2374192  
SET timestamp=1281764222;  
select count(distinct ad_code) as x from ad_visit_history where ad_code in (select ad_code from ad_list where media_id=15);  
# Time: 100814 13:37:16  
# User@Host: root[root] @ localhost []  
# Query_time: 4.608920 Lock_time: 0.000078 Rows_sent: 1 Rows_examined: 1260544  
SET timestamp=1281764236;  
select count(*) as cou from ad_visit_history where ad_code in (select ad_code from ad_list where id=41) order by id desc;

Option h requires an argument  
ERROR: bad option 
  
Usage: mysqldumpslow [ OPTS... ] [ LOGS... ]  
  
Parse and summarize the MySQL slow query log. Options are  
  
 --verbose verbose  
 --debug debug  
 --help write this text to standard output  
  
 -v verbose  
 -d debug //Error checking -s ORDER what to sort by (t, at, l, al, r, ar etc), 'at' is default //Sorting method: query times, time, lock time and number of records returned -r reverse the sort order (largest last instead of first) //Reverse sort -t NUM just show the top n queries //Show the top N queries -a don't abstract all numbers to N and strings to 'S' 
 -n NUM abstract numbers with at least n digits within names //Abstract numbers, at least n digits within the name -g PATTERN grep: only consider stmts that include this string //Configuration mode -h HOSTNAME hostname of db server for *-slow.log filename (can be wildcard), //MySQL machine name or IP 
 The default is '*', ie match all 
 -i NAME name of server instance (if using mysql.server startup script) 
 -l don't subtract lock time from total time //Do not subtract lock time from total time