The DBUG Package Adding to “all macros enabled”  results in no change: Disabling all enabled macros disables the  d  flag entirely: mysql>  SET debug = ’d,error,loop’; mysql>  SELECT @@debug; +--------------+ | @@debug | +--------------+ | d,error,loop | +--------------+ mysql>  SET debug = ’-d,error,loop’; mysql>  SELECT @@debug; +---------+ | @@debug | +---------+ | | +---------+ mysql>  SET debug = ’d’; mysql>  SELECT @@debug; +---------+ | @@debug | +---------+ | d | +---------+ mysql>  SET debug = ’+d,loop’; mysql>  SELECT @@debug; +---------+ | @@debug | +---------+ | d | +---------+ +----------------------+ | @@debug | +----------------------+ | d,error,warning,loop | +----------------------+ mysql>  SET debug = ’-d,error,loop’; mysql>  SELECT @@debug; +-----------+ | @@debug | +-----------+ | d,warning | +-----------+ 1168