What is the invoice number and invoice date for the invoice with most number of transactions?
return invoices ;return transactions of  #1 ;return number of  #2 for each  #1 ;return #1 where #3 is  highest ;return invoice   number of  #4 ;return invoice   date of  #4 ;return #5 ,  #6
['select', 'project', 'group', 'superlative', 'aggregate', 'project', 'union']