What state or province are the most customer addresses located?
select state_province_county, count(*) from customer_addresses as t1 join addresses as t2 on t1.address_id = t2.address_id group by state_province_county order by count(*) desc limit 1
How many customers have addresses in the state of California
select count(*) from customers as t1 join customer_addresses as t2 on t1.customer_id = t2.customer_id join addresses as t3 on t2.address_id = t3.address_id where t3.state_province_county = 'California'
What are their names and phone numbers?
select t1.customer_name, t1.customer_phone from customers as t1 join customer_addresses as t2 on t1.customer_id = t2.customer_id join addresses as t3 on t2.address_id = t3.address_id where t3.state_province_county = 'California'