CREATE TABLE email1
(
details varchar(30)
);
INSERT INTO email1
(details)
VALUES
('admin1@sqlfiddle.com');
INSERT INTO email1
(details)
VALUES
('admin2@sqlfiddle.com');
INSERT INTO email1
(details)
VALUES
('admin3@sqlfiddle.com');
INSERT INTO email1
(details)
VALUES
('admin4@sqlfiddle.com');
CREATE TABLE email2
(
details varchar(30)
);
INSERT INTO email2
(details)
VALUES
('admin1@sqlfiddle.com');
INSERT INTO email2
(details)
VALUES
('admin2@sqlfiddle.com');
select * from email1 where details not in (select details from email2)