2405567 - Too excessive logging rows, due to 'ignore constraint ... unique ...'. -- SAP IQ

A custonmer faced a loading session was out of control with holding lock table for more than 8 hours.
   Finally customer did re-start IQ server due to this problem.
  
   DBA found the status was caused when a load sql ran with 'ignore constraint ... unique ...'
   and 'ONLY LOG unique' option. By mistaken, customer executed a loading which has almost duplicate data.
   Therefore the problem load session was writing too much violation data to file-system file due to 'only log unique' option.
   In customer case, the flat file had about 100 million rows and It seemed most of rows were writing to file. 
   Such big writing to filesystem file seemed to cause slowness server and out of control of the session.  
   It seemed the data logging operation was not accept cancellation signal.

   Following is customer's load query.
   
       Load TABLE TB...A
       ( ... )
       from '/.../TB...A_all.dat'
       ignore constraint Unique 3, Check 10, NULL 10, Foreign Key 10 , Data Value 10
       only log unique
       ...
       row log '.../err_row.log'
       ... ;

SAP IQ16

"ignore constraint" ; "only log unique" ; , KBA , BC-SYB-IQ , Sybase IQ , Problem