content_image/856917.jpg
--debug=d:f,main,subr1:F:L:t,20 --debug=d,input,output,files:n --debug=d:t:i:O,\\mysqld.trace 

For mysqld , it is also possible to change DBUG settings at runtime by setting the debug  system variable. This variable has global and session values: 

mysql> SET GLOBAL debug = ’ debug_options ’; mysql> SET SESSION debug = ’ debug_options ’; 

Changing the global debug  value requires privileges sufficient to set global system variables. Changing the session debug  value requires privileges sufficient to set restricted session system variables. See Section 5.1.9.1, “System Variable Privileges” . 

The debug_options  value is a sequence of colon-separated fields: 

field_1:field_2:...:field_ N 

Each field within the value consists of a mandatory flag character, optionally preceded by a +  or - character, and optionally followed by a comma-separated list of modifiers: 

[+|-]flag[,modifier,modifier,...,modifier] 

The following table describes the permitted flag characters. Unrecognized flag characters are silently ignored. 

<img src='content_image/856917.jpg'>

