Displays the slow query status and log directory

show variables like '%slow_query_log%';
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+---------------------+--------------------------------------+
| Variable_name       | Value                                |
+---------------------+--------------------------------------+
| slow_query_log      | OFF                                  |
| slow_query_log_file | /var/lib/mysql/9e6bec7d7160-slow.log |
+---------------------+--------------------------------------+
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Enabling Slow Query

Description: 1 open; 0 close;

set global slow_query_log = 1;
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Display slow query threshold in seconds

By default, a log is generated only when the execution time exceeds 10 seconds

show variables like '%long_query%';
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+-----------------+-----------+
| Variable_name   | Value     |
+-----------------+-----------+| long_query_time | | + 10.000000-----------------+-----------+
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Set the slow query threshold

Note: You need to restart the mysql client to get the latest values

set global long_query_time = 0.8;
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Check whether deadlock logging is enabled

show variables like "%innodb_print_all_deadlocks%";
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+----------------------------+-------+
| Variable_name              | Value |
+----------------------------+-------+
| innodb_print_all_deadlocks | OFF   |
+----------------------------+-------+
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Enable record deadlock
set global innodb_print_all_deadlocks=1
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