MongoDB + Laravel + jenssegers/laravel-mongodb + update nested child elements - mongodb

Question

Hellow folks, I am new to MongoDB and looking for some answer
Is there any way to update nested array without looping it.
foreach ($post->comments as $key => $comment) {
if ($comment['posted_by'] == $authUser['id']) {
$data = $post->update([
"comments.$key.description" => $dataArray['description'],
"comments.$key.updated_at" => $dataArray['updated_at'],
]);
}}
I want to to do something like below.
$post = Post::where('_id', $id)->where('comments.*.id', $commentId)->update(array('description' => $desc));
Or I have to write raw MongoDB query for that.
I have 1 level nested comment also under main comments so if I want to update nested comment than I have to loop comment array than the nested comment array.
if ($subCommentId) {
foreach ($comment as $nestedkey => $nestedComments) {
if ($nestedComments['id'] === $subCommentId && $nestedComments['posted_by'] == $authUser['id']) {
$data = $post->update([
"comments.$key.$nestedkey.description" => $dataArray['description'],
"comments.$key.$nestedkey.updated_at" => $dataArray['updated_at'],
]);
}
}
}
Something like this :
$post = Post::where('_id', $id)->where('comments.*.id', $commentId)->where('comments.*.*.id', $subCommentId)->update(array('description' => $desc));
Is it good to store comment in the same collection as an array or should I create a new collection for that as maximum BSON document size is 16 megabytes and how much comments it can store like 10K or more?
Below is my sample comment array format under one Collection.
"comments" : [
{
"description" : "description some",
"channel" : "swachhata-citizen-android",
"user_role" : "Citizen",
"id" : "5b4dc367d282f",
"user_role_id" : ObjectId("5accd7f8309a203be03b6441"),
"created_at" : "2018-07-17 15:52:31",
"updated_at" : "2018-07-17 15:52:31",
"ip_address" : "127.0.0.1",
"user_agent" : "PostmanRuntime/6.4.1",
"deleted" : false,
"channel_id" : "5acccfe4309a2038347a5c47",
"posted_by" : NumberInt(1),
"comments" : [
{
"description" : "some description nested",
"channel" : "swachhata-citizen-android",
"user_role" : "Citizen",
"id" : "5b4dcfc7022db",
"user_role_id" : ObjectId("5accd7f8309a203be03b6441"),
"created_at" : "2018-07-17 16:45:19",
"updated_at" : "2018-07-17 16:45:19",
"ip_address" : "127.0.0.1",
"user_agent" : "PostmanRuntime/6.4.1",
"deleted" : false,
"channel_id" : "5acccfe4309a2038347a5c47",
"posted_by" : NumberInt(1)
}
]
}
]
Thanks. :)

Answer 1

To update nested document, you should use arrayFilters:
Post::raw()->updateMany(
[],
[ '$set' => ["comments.$[i].comments.$[j].description" => $desc] ],
[ '$arrayFilters' => [
[
[ "i.id" => "5b4dc367d282f" ],
[ "j.id" => "5b4dcfc7022db" ]
]
]
]
)
Hope it helps :)