a. The query must either not be an administrative statement, or --log-slow-adminstatements must have been specified. b. The query must have taken at least long_query_time seconds, or log_queries_not_using_indexes must be enabled and the query used no indexes for row lookups. c. The qu...
The slow query log consists of SQL statements that took more thanlong_query_timeseconds to execute and required at leastmin_examined_row_limitrows to be examined. The minimum and default values oflong_query_timeare 0 and 10, respectively. The value can be specified to a resolution of microse...
a. The query must either not be an administrative statement, or --log-slow-adminstatements must have been specified. b. The query must have taken at least long_query_time seconds, or log_queries_not_using_indexes must be enabled and the query used no indexes for row lookups. c. The qu...
slow_query_log：是否开启慢查询日志，1表示开启，0表示关闭。log-slow-queries ：旧版（5.6以下版本...
当主从复制采用 binlog 的行模式时,如果从库启用 slow_query_log、log_slow_replica_statements 且从库重放 CREATE TABLE、DROP TABLE 时因特殊情况(比如被从库其他 SQL 占用 MDL 锁)执行耗时较长,会被从库记录到慢日志(slow log),而 ALTER TABLE 却不会被记录到慢日志。
The slow query log consists of SQL statements that took more than long_query_time seconds to execute and required at least min_examined_row_limit rows to be examined. The minimum and default values of long_query_time are 0 and 10, respectively. The value can be specified to a resolution ...
slow_query_log Command-Line Format--slow-query-log[={OFF|ON}]System Variable slow_query_log ScopeGlobalDynamic YesSET_VARHint Applies No Type BooleanDefaultValueOFF 可见long_query_time的Scope= Global, Session,全局和会话级别;slow_query_log的Scop=Global只是全局级别;我们需要close掉老连接,这样新打开...
*慢查询日志(slow query log) *通用查询日志(general query log) 1.作用: 通用查询日志用来记录用户的所有操作 ,包括启动和关闭MySQL服务、所有用户的连接开始时间和截止时间、发给 MySQL 数据库服务器的所有 SQL 指令等。当我们的数据发生异常时,查看通用查询日志,还原操作时的具体场景,可以帮助我们准确定位问题。
This had the same EXPLAIN report. It took 1 or 2 iterations to warm the buffer pool, but then the performance of the query tripled. This executed in 0.16 seconds. I also tried removing the USE INDEX, and the time increased slightly, to 0.17 seconds. ...
The query must either not be an administrative statement, or --log-slow-admin-statements must have been specified. The query must have taken at least long_query_time seconds, or log_queries_not_using_indexes must be enabled and the query used no indexes for row lookups. Th...