Slow query - MySQL
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What is slow query?
https://dev.mysql.com/doc/refman/8.0/en/slow-query-log.html
The definition “slow query” is “SQL statements that take more than long_query_time seconds to execute and require at least min_examined_row_limit rows to be examined”.
Configure
Check current status
SHOW VARIABLES LIKE "slow_query_log";
SHOW VARIABLES LIKE "slow_query_time";
SHOW VARIABLES LIKE "slow_query_log_file";
Enable to log slow queries
Logging slow queries which take more than 10 seconds.
SET GLOBAL slow_query_log = 'ON';
SET GLOBAL long_query_time = 10;
SET GLOBAL slow_query_log_file = '/path/filename';
A sample line in the log file:
# User@Host: atlex00[atlex00] @ [192.168.0.123] Id: 123456789
# Query_time: 12.34556 Lock_time: 0.000083 Rows_sent: 0 Rows_examined: 1234567
SELECT .... {{ long_query_content }}