I have two tables Notification and Worker Notifications. On those tables there are two similar columns called Time. My worker class inherits Notification and I would like to join all preexisting times on worker with notification time.
id | Worker| Time
-------------
10 | John| 8/17/2019
20 | Rui| 8/17/2019
30 | Pen| 8/17/2019
id | Notification| Time |WorkerID
-----------------------------------
10 | John| 8/17/2019 | 10
20 | Rui| 8/17/2019 |20
30 | Pen| 8/17/2019 |30
SELECT category_id, col1, col2, col3 FROM items_a UNION SELECT category_id, col1, col2, col3 FROM items_b
I dare say it should actually be
SELECT *
FROM
worker w
INNER JOIN
notifications n
ON
w.id = n.workerid
I say this because a notification has a workerid so it clearly "belongs to a worker" - it isn't necessarily related to a worker based on the time, as if two times are the same then you could end up joining a notification assigned to John, to Dave intead
But if you insist on joining on the time the pattern is the same:
SELECT *
FROM
worker w
INNER JOIN
notifications n
ON
w.time = n.time
JOIN causes your result set to grow sideways (more columns). UNION causes your result set to grow vertically (more rows)
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