SQL JOIN each id in JSON object - sql

Question

I have a JSON column containing col_values for another table. I want to return rows from that other table for each item in the JSON object.
If this was an INT column, I would use JOIN, but I need to JOIN every entry in the JSON object.
Take:
writers :
| id | name | projects (JSON) |
|:-- |:-----|:------------------|
| 1 | Andy | ["1","2","3","4"] |
| 2 | Hank | ["3","4","5","6"] |
| 3 | Alex | ["1","7","8","9"] |
| 4 | Joe | ["1","5","6","7"] |
| 5 | Ken | ["2","4","5","6"] |
| 6 | Zach | ["2","7","8","9"] |
| 7 | Walt | ["2","5","6","7"] |
| 8 | Mike | ["2","3","4","5"] |
cities :
| id | name | project |
|:-- |:---------|:--------|
| 1 | Boston | 1 |
| 2 | Chicago | 2 |
| 3 | Cisco | 3 |
| 4 | Seattle | 4 |
| 5 | North | 5 |
| 6 | West | 6 |
| 7 | Miami | 7 |
| 8 | York | 8 |
| 9 | Tainan | 9 |
| 10 | Seoul | 1 |
| 11 | South | 2 |
| 12 | Tokyo | 3 |
| 13 | Carlisle | 4 |
| 14 | Fugging | 5 |
| 15 | Turkey | 6 |
| 16 | Paris | 7 |
| 17 | Midguard | 8 |
| 18 | Fugging | 9 |
| 19 | Madrid | 1 |
| 20 | Salvador | 2 |
| 21 | Everett | 3 |
I need every city ordered by name for Mike (id=8).
Desired results:
This is what I'm getting and what I need to get (ORDER BY name).
Output :
| id | name | project |
|:---|:---------|:--------|
| 13 | Carlisle | 4 |
| 2 | Chicago | 2 |
| 3 | Cisco | 3 |
| 21 | Everett | 3 |
| 14 | Fugging | 5 |
| 5 | North | 5 |
| 20 | Salvador | 2 |
| 4 | Seattle | 4 |
| 11 | South | 2 |
| 12 | Tokyo | 3 |
Current query, but this can't be the best way...
SQL >
SELECT c.*
FROM cities c
WHERE EXISTS (
SELECT 1
FROM writers w
WHERE JSON_CONTAINS(
w.projects, CONCAT('\"', c.project, '\"'))
AND w.id = '8'
)
ORDER BY c.name;
DB Fiddle with the above. Is there a better way to do this "properly"?
Background
If it matters, I need to keep using JSON as the datatype because my server-side software that uses this database normally reads that column best if presented as a JSON object.
I would normally just do several database calls and iterate through that JSON object in my server-side language, but that is way too expensive with so many database calls, notwithstanding that it is even more costly to do multiple database calls for pagination.
I need all the results in a single database call. So, I need to JOIN or otherwise loop through each item in the JSON object within SQL.

Answer 1

Start with JOIN
Per a comment from a user, there is a better way...
SQL >
SELECT c.*
FROM writers w
JOIN cities c ON JSON_CONTAINS(w.projects, CONCAT('\"', c.project, '\"'))
WHERE w.id = '8'
ORDER BY c.name;
Output is the same...
Output :
id
name
project
13
Carlisle
4
2
Chicago
2
3
Cisco
3
21
Everett
3
14
Fugging
5
5
North
5
20
Salvador
2
4
Seattle
4
11
South
2
12
Tokyo
3
DB Fiddle