【MySQL】MySQL8确认哪些参数在使用以及来源

在MySQL8中，参数可能来自不同的地方，确认有效的参数来自于哪里：

SELECT
	variable_name,
	variable_source AS source,
	variable_path,
	set_time,
	set_user AS USER,
	set_host 
FROM
	PERFORMANCE_SCHEMA.variables_info;

例如，查看到底使用哪个参数配置文件：

SELECT
	variable_path,
	variable_source,
	count(*) 
FROM
	PERFORMANCE_SCHEMA.variables_info 
WHERE
	length( variable_path )!= 0 
GROUP BY
	variable_path,
	variable_source;