my $grammar = q {
    
    select          : /SELECT/i select_list /FROM/i table_source

    
    select_list     : column(s /,/)
                      
    
    column          : identifier /=/ col_name
                    | col_name /AS/i alias
                    | col_name alias(?)
                    | string
                    | number
    
    
    table_source    : table alias(?) with_hint(?) table_join(s?)
					| table alias(?) table_join(s)
					| table alias(?) /,/ table_list
					| table alias(?)

yada...yada...

##</code><code>##

select colA, colB, colC from customer x