CREATE TABLE customer (cust_id TEXT, cust_name TEXT, acc_type TEXT, acc_bal DECIMAL, no_of_loans DECIMAL, credit_score DECIMAL, branch_id DECIMAL, state TEXT)
CREATE TABLE bank (branch_id DECIMAL, bname TEXT, no_of_customers DECIMAL, city TEXT, state TEXT)
CREATE TABLE loan (loan_id TEXT, loan_type TEXT, cust_id TEXT, branch_id TEXT, amount DECIMAL)

Find the state which has the most number of customers.
SELECT state FROM bank GROUP BY state ORDER BY SUM(no_of_customers) DESC LIMIT 1
SELECT "state" FROM "bank" GROUP BY "state" ORDER BY SUM("no_of_customers") DESC NULLS LAST LIMIT 1