PHP SQL left join fetch all - php

Question

I have 3 mysql tables from where I am trying to fetch data
Table: list
list_id | name | description
-------------------------------------
1234 | name1 | sample description1
1235 | name2 | sample description2
Table: list_to_category
id | list_id | category_id
--------------------------------
1 | 1234 | 1
2 | 1234 | 2
3 | 1234 | 3
4 | 1235 | 2
5 | 1235 | 3
And table: category
id | title | parent_id
--------------------------------
1 | Category 1 | 0
2 | Category 2 | 0
3 | Category 3 | 0
And from PHP SQL query I want to fetch data like below
1. name1 - category 1, category 2, category 3
2. name2 - category 2, category 3
I tried below query
SELECT list.name, category.title FROM list
LEFT JOIN list_to_category
ON list.id = list_to_category.list_id
LEFT JOIN category
ON list_to_category.id = category.id
This gives me only single category name assigned to a list like this
1. name1 - category 1
2. name2 - category 2
Is it possible in single query?

Answer 1

You can use GROUP_CONCAT for this:
select
l.list_id,
l.name,
group_concat(distinct c.title) categories
from list l
left join list_to_category lc
on l.list_id = lc.list_id
left join category c
on lc.category_id = c.id
group by l.list_id

Answer 2

You can try this solution.
select l.list_id, l.name, (select group_concat(c.title) from list_to_category ltc JOIN category c ON c.id=ltc.category_id where ltc.list_id=l.id) from list l
Hope this will help you!!!

Answer 3

Use GROUP_CONCAT for group by "name" to fetch result :
SELECT L.name, GROUP_CONCAT(C.title) as title FROM list L
LEFT outer JOIN list_to_category LC ON L.list_id = LC.list_id
LEFT outer JOIN category C ON LC.category_id = C.id
group by L.name
Use GROUP_CONCAT for group by "list_id" for same name of list to fetch result :
SELECT L.name, GROUP_CONCAT(C.title) as title FROM list L
LEFT outer JOIN list_to_category LC ON L.list_id = LC.list_id
LEFT outer JOIN category C ON LC.category_id = C.id
group by L.list_id

Answer 4

It should be apparent from the code below that I'm no PHP coder. However, this should get the idea across. You can also use javascript/css to handle the transformation, which means things can be even more dynamic...
Oh, and I changed some table/column names - because I like it better that way...
<?php
require('path/to/connection/statements'); // $con
$query = "
SELECT l.list_id
, l.name
, l.description
, c.category_id
, c.title
, c.parent_id
FROM list l
JOIN list_category lc
ON lc.list_id = l.list_id
JOIN category c
ON c.category_id = lc.category_id
ORDER
BY l.list_id
, c.category_id;
";
$result = mysqli_query($con,$query);
$my_array = array();
while($row = mysqli_fetch_assoc($result)){
$my_array[] = $row;
}
$new_array = array();
foreach ($my_array as $row)
{
$new_array[$row['list_id']][$row['name']][$row['description']][] = $row['title'];
}
print_r($new_array);
?>
This will turn an array like this:
Array
(
[0] => Array
(
[list_id] => 1234
[name] => name1
[description] => sample description1
[category_id] => 1
[title] => Category 1
[parent_id] => 0
)
[1] => Array
(
[list_id] => 1234
[name] => name1
[description] => sample description1
[category_id] => 2
[title] => Category 2
[parent_id] => 0
)
[2] => Array
(
[list_id] => 1234
[name] => name1
[description] => sample description1
[category_id] => 3
[title] => Category 3
[parent_id] => 0
)
[3] => Array
(
[list_id] => 1235
[name] => name2
[description] => sample description2
[category_id] => 2
[title] => Category 2
[parent_id] => 0
)
[4] => Array
(
[list_id] => 1235
[name] => name2
[description] => sample description2
[category_id] => 3
[title] => Category 3
[parent_id] => 0
)
)
...into an array like this...
Array
(
[1234] => Array
(
[name1] => Array
(
[sample description1] => Array
(
[0] => Category 1
[1] => Category 2
[2] => Category 3
)
)
)
[1235] => Array
(
[name2] => Array
(
[sample description2] => Array
(
[0] => Category 2
[1] => Category 3
)
)
)
)

Answer 5

try this code
select l.name,c.title
from list_to_category lc join list l on lc.list_id=l.id
join category c on lc.catg_id=c.id