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CREATE TABLE messages (messageid INTEGER PRIMARY KEY AUTO_INCREMENT
, message VARCHAR(150)
, sender VARCHAR(40)
, recipient VARCHAR(40))
CREATE TABLE employees (employeeid INTEGER PRIMARY KEY
, employeename VARCHAR(40)
, area VARCHAR(40))
insert into employees values (1, 'Mark', 'Maintenance')
insert into employees values (2, 'Ann', 'Maintenance')
INSERT INTO messages (message
, sender
, recipient)
VALUES ("Message."
, "System"
, (SELECT employeename
FROM employees
WHERE area = "Maintenance"
and employeeid = 1))
INSERT INTO messages (message
, sender
, recipient)
VALUES ("Message."
, "System"
, (SELECT max(employeename)
FROM employees
WHERE area = "Maintenance"))
select * from messages
| messageid | message | sender | recipient |
|---|---|---|---|
| 1 | Message. | System | Mark |
| 2 | Message. | System | Mark |