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What is the purpose of the slow query log?
5.4.5 The Slow Query Log. The slow query log consists of SQL statements that take more than long_query_time seconds to execute and require at least min_examined_row_limit rows to be examined. The slow query log can be used to find queries that take a long time to execute and are therefore candidates for optimization.
How to write slow admin statements in MySQL?
If a log file already is open, it is closed and the new file is opened. The server writes less information to the slow query log if you use the –log-short-format option. To include slow administrative statements in the slow query log, enable the log_slow_admin_statements system variable.
What are the administrative statements in slow query?
Administrative statements include ALTER TABLE , ANALYZE TABLE , CHECK TABLE , CREATE INDEX , DROP INDEX , OPTIMIZE TABLE, and REPAIR TABLE . To include queries that do not use indexes for row lookups in the statements written to the slow query log, enable the log_queries_not_using_indexes system variable.
How is the query time measured in MySQL?
The query time is measured from after any initial table locks have been acquired. Queries are written to the slow query log after all locks have been released. This reduces the time locks are held, but means that two queries requiring the same table locks may end up in the slow query log in opposite order.
Where can I find slow query logs in azure?
Azure Monitor Diagnostic Logs allows you to pipe slow query logs to Azure Monitor Logs (Log Analytics), Azure Storage, or Event Hubs. See below for more information. When logging to the server’s local storage, logs are available for up to seven days from their creation.
How to disable slow query log in MySQL?
Set slow_query_log to 0 to disable the log or to 1 to enable it. Set slow_query_log_file to specify the name of the log file. If a log file already is open, it is closed and the new file is opened. The server writes less information to the slow query log if you use the –log-short-format option.
How to set slow query log filename in MariaDB?
For example: Another way to configure the slow query log filename is to set the log-basename option, which configures MariaDB to use a common prefix for all log files (e.g. slow query log, general query log, error log, binary logs, etc.). The slow query log filename will be built by adding -slow.log to this prefix.