How to write SQL select?

Question

SQL

Hello! Faced such a problem.
There are two tables: topic and topic_tag

and

They are related by topic_id
field I need to select all elements from topic if it has one of given tags (For example, IN('website', 'demo', 'test'))
I tried to do So:

SELECT DISTINCT
  t.topic_id
FROM
  topic as t
JOIN topic_tag as tag on tag.topic_id = t.topic_id AND tag.topic_tag_text IN  ('сотрудники', 'Директор')
WHERE
  1=1
ORDER BY t.topic_id desc
LIMIT 0, 10

And when I want to make a selection on the second page LIMIT 1, 10, then the selection is no different. Can you suggest what can be done?

Answer 1

LIMIT <первая_запись>, <количество_записей>
Given that the records are numbered from 1, the selections LIMIT 0, 10and are LIMIT 1, 10equivalent.

Answer 2

You overdid it with the request. If you only need topic_id from 1 table, you don't need to join at all to do
SELECT t.topic_id FROM topic as t
WHERE
t.topic_id in (SELECT topic_id FROM topic_tag WHERE topic_tag_text IN ('employees', 'Director')) ORDER BY t. topic_id desc
Run a request in phpmyadmin and see how the limit is set there when switching pagination, it will be clear how you need to do it.