Can you tell me how many different purchases Lucas Mancini has made?
select count ( * ) from invoices as t2 join customers as t1 on t1.id = t2.customer_id where t1.first_name = "Lucas" and t1.last_name = "Mancini"
Great!  How much total money has Lucas Mancini spent in total?
select sum ( t2.total ) from customers as t1 join invoices as t2 on t1.id = t2.customer_id where t1.first_name = "Lucas" and t1.last_name = "Mancini"
What was the most recent associated invoice date for Lucas Mancini?
select t2.invoice_date from customers as t1 join invoices as t2 on t1.id = t2.customer_id where t1.first_name = "Lucas" and t1.last_name = "Mancini" order by t2.invoice_date desc limit 1