how to limit the number of entries in the for loop php - php

Question

I have a model and ready-made data in a table. In this model, I added a new field and made a connection with another table.
And in order not to manually fill in these fields for each record, I want to create a migration that will automatically fill in this field for all records.
Relationship table has two fields: post_id and author_id.
I am trying to do like this:
$posts = Posts::find()->all();
foreach ($posts as $index => $post) {
for($i = 0, $j = 0; $i < $index; $j++, $i++) {
if ($j >= 4) {
$j = 0;
}
$item = new PostAuthor();
$item->setAttribute('post_id', $posts->id);
$item->setAttribute('author_id', $j + 1);
$item->save();
}
}
Everything also works as it should, but there is one problem, when the counter reaches 4, then the author_id is added again to the same post, starting from one.
I am attaching a screenshot, what should not be circled at all, when the counter reaches 4, then the post does not need to add an author_id anymore

Answer 1

Because
if ($j >= 4) {
$j = 0;
}
does nothing other than set $j = 0. The loop carries on as-written.
If you want the loop to halt here, then you have two options:
foreach ($posts as $index => $post) {
for($i = 0, $j = 0; $i < $index; $j++, $i++) {
if ($j >= 4) {
break;
}
// ...
}
}
or
foreach ($posts as $index => $post) {
for($i = 0, $j = 0; $i < $index, $j < 4; $j++, $i++) {
// ...
}
}
Though at this point $i and $j are functionally identical and you can simply throw one of them away and put an && in the loop boundary condition.
foreach ($posts as $index => $post) {
for($i = 0; $i < $index && $i < 4; $i++) {
// ...
}
}