param('key_column'): If every line of your input is a list (it happens, for example, when your SQL returns multiple columns or you have set the 'delimiter' in file/cmd mode)
this is the way to say which column is undergoing 'ranging'
param('hashed_column_number'): if defined, turns 'hashed_column_number' into a dir_revhash and appends it to the list of fields.
# The following 4 parameters are mutually exclusive and define the source of ids for the jobs:
param('inputlist'); The list is explicitly given in the parameters, can be abbreviated: 'inputlist' => ['a'..'z']
...
...
@@ -89,6 +94,8 @@ sub run {
my$key_column=$self->param('key_column')||0;
my$delimiter=$self->param('delimiter');
my$hashed_column_number=$self->param('hashed_column_number');# skip this step if undefined