SQL LEFT JOIN without duplicating same row values - php

Question

I was wondering if someone can help me with my problem that is as follows:
I want to pull once posts.text and uids which belongs to that posts.text but when I execute the code below it does this: eg. there are 4 uids that belongs to the post so I get the posts.text four times instead of once.
$query = mysqli_query($con,
"SELECT posts.text, relationships.uidb
FROM posts
LEFT JOIN relationships
ON posts.uid=relationships.uida
LIMIT 10");
if(mysqli_num_rows($query) > 0){
while($row = mysqli_fetch_assoc($query)){
echo $row['text']." ".$row['uidb']."<br>";
}
}
I would really appreciate any help.
Thanks is advance.
Peter
Update:
Desired output would be like this:
postsArray[0]->text = //post text
postsArray[1]->text = //another post text
postsArray[0]->uids[0] = //approved uid for first post
postsArray[0]->uids[1] = //another approved uid for first post
now it outputs this:
text 10
text 15
text 12
and I want this:
text 10, 15, 12

Answer 1

One way is to use Mysql's GROUP_CONCAT which provides comma separated values list for each group i.e (p.uid)
$query = mysqli_query($con,
"SELECT p.text, GROUP_CONCAT(r.uidb SEPARATOR ', ') uidbs
FROM posts p
LEFT JOIN relationships r
ON p.uid=r.uida
GROUP BY p.uid
LIMIT 10");
if (mysqli_num_rows($query) > 0) {
while ($row = mysqli_fetch_assoc($query)) {
echo $row['text'].' '.$row['uidbs'];
/*$uidbs= explode($row['uidbs'],',');
foreach ($uidbs as $key => $val) {
echo $val.' ';
}*/
echo '</br>';
}
}
GROUP_CONCAT
According to docs The result is truncated to the maximum length that
is given by the group_concat_max_len system variable, which has a
default value of 1024. The value can be set higher, although the
effective maximum length of the return value is constrained by the
value of max_allowed_packet.

Answer 2

Maybe this might work for you:
$query = mysqli_query($con,
"SELECT posts.text, relationships.uidb
FROM posts
LEFT JOIN relationships
ON posts.uid=relationships.uida
GROUP BY posts.uid
LIMIT 10");
if(mysqli_num_rows($query) > 0){
while($row = mysqli_fetch_assoc($query)){
echo $row['text']." ".$row['uidb']."<br>";
}
}

Answer 3

SELECT posts.text, relationships.uidb
FROM posts
LEFT JOIN relationships
ON posts.uid=relationships.uida
GROUP BY posts.primary_key_of_your_post
LIMIT 10

Answer 4

You should call 2 queries. In your first query, call the text, and then call uids.
You should not write complex queries because this will make your business more complex and you will not maintain your code in future.