按照MySQL官方文档可将my.ini(Microsoft Windows)或my.cnf(UNIX/Linux)中mysqld段的log-warnings设置为1以上的数字，如2，重启mysqld生效。

• , -W [level]

  Command-Line Format：--log-warnings[=#] 或-W [#]

  Option-File Format：log-warnings[=#]

  System Variable Name：

       Type：numeric

       Default：1

       32-bit Range：0 .. 4294967295

       64-bit Range：0 .. 18446744073709547520

Print out warnings such as Aborted connection... to the error log. This option is enabled (1) by default. To disable it, use . Specifying the option without a level value increments the current value by 1. Enabling this option by setting it greater than 0 is recommended, for example, if you use replication (you get more information about what is happening, such as messages about network failures and reconnections). If the value is greater than 1, aborted connections are written to the error log. See .

If a slave server was started with enabled, the slave prints messages to the error log to provide information about its status, such as the binary log and relay log coordinates where it starts its job, when it is switching to another relay log, when it reconnects after a disconnect, and so forth. As of MySQL 5.1.38, the server logs messages about statements that are unsafe for statement-based logging if is greater than 0.

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