MySQL 5.6

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create table sales_flat_order(id int, status varchar(100), customer_email varchar(100));
insert into sales_flat_order(id, status, customer_email) values(1, 'holded', 'test@example.com');
insert into sales_flat_order(id, status, customer_email) values(2, 'holded', 'test@example.com');
insert into sales_flat_order(id, status, customer_email) values(3, 'holded', 'test@example.com');
insert into sales_flat_order(id, status, customer_email) values(4, 'invoiced', 'test4@example.com');
insert into sales_flat_order(id, status, customer_email) values(5, 'complete', 'test4@example.com');
insert into sales_flat_order(id, status, customer_email) values(6, 'sent', 'test5@example.com');

SELECT customer_email 
FROM   sales_flat_order 
WHERE  customer_email NOT IN (SELECT customer_email
                              FROM   sales_flat_order
                              WHERE  status != 'holded');
                              
SELECT customer_email 
FROM   sales_flat_order 
WHERE  customer_email NOT IN ('whatever', 'foobar', '123@456.com');

customer_email
test@example.com
test@example.com
test@example.com

customer_email
test@example.com
test@example.com
test@example.com
test4@example.com
test4@example.com
test5@example.com