MYSQL Group By same id? - php

Question

I have the following 2 tables :
TABLE 1: user
id s_id first_name last_name
----------------------------------
1 2 test test
2 2 hello test
3 2 now hello
4 1 john smith
TABLE 2: section
id section_name
-------------------
1 first
2 my section
3 other section
based on the above two tables , I would like to write a MYSQL query to :
SELECT ALL from user table and GROUP THEM BY s_id ( SAME s_id) , how could I do that?
I would like to get all the s_id = 2 ALL grouped together as an array or object but controlled by s_id? so I would loop through the s_ids and print out the first and last name?
Here is an Example of the output:
$sections = array['my section'](array('first_name'=>'test' , 'last_name'=>'test'),
array('first_name'=>'hello' , 'last_name'=>'test'),
array('first_name'=>' now' , 'last_name'=>'hello'))
thanks

Answer 1

Simply
SELECT * FROM `user` GROUP BY `s_id`
But you have different question in your title and in your content.
So what you want in PHP is something like this:
while($row = your sql fetch)
{
$array[$row['s_id']][] = array('first_name' => $row['first_name'], 'last_name' => $row['last_name']);
}
print_r($array);

Answer 2

If you need all the users with s_id = 2 than:
SELECT * FROM `user` where `s_id` = 2 # this will give 3 users
otherwise if you group with s_id you'll get only one user for each section, and I think you don't want that
To show all, than you have to run query :
SELECT user.*, section.section_name FROM `user`
INNER JOIN section ON section.id = user.s_id
And trick it in PHP:
$query = "
SELECT
user.*,
section.section_name
FROM `user`
INNER JOIN section
ON section.id = user.s_id
";
$result = mysqli_query($conn, $query);
$final_data = array();
while($data = mysqli_fetch_assoc($result))
{
$final_data[$data['section_name']][] = $data;
}
print($final_data); // to see the result

Answer 3

Take a look at mysqli_fetch_array function in php.
You need to cycle the query result with this php function and put them in an array, you do not need to group anything in sql, but only:
select * from user order by s_id
In the php cycle you can populate your array as you need.