Hi, i have a problem to take data from relationship belongstomany, i try take data when i edit post and i have this error this '1052 Column 'id' in field list is ambiguous'.
error:SQLSTATE[23000]: Integrity constraint violation: 1052 Column 'id' in field list is ambiguous
SELECT `id` FROM `tags` INNER JOIN `post_tag` ON `tags`.`id` = `post_tag`.`` WHERE `post_tag`.`` = 6
code:
@foreach ($tagSelect as $tagSe)
<option value="{{$tagSe->id}}" {{($post->tags()->pluck('id')->contains($tagSe->id)) ? 'selected' : ''}}>
{{$tagSe->name }}
</option>
@endforeach```
not sure about the error, but what you are doing will give an n+1 issue as you query the database on every loop through the foreach.
In the controller, load the post tags and then just do the compare in the loop
@foreach ($tagSelect as $tagSe)
<option value="{{$tagSe->id}}" {{ $post->tags->contains('id', $tagSe->id) ? 'selected' : ''}}>
{{$tagSe->name }}
</option>
@endforeach```
The ambiguity is solved by speciying the table name from where you want to retrieve the id field. Probably your pivot table (post_tag) also has a column named id, so SQL does not know which id column to retrieve.
->pluck('tags.id')
But please consider, and read carefully @snapey answer. It is a much better approach.
In your current code you are executing a different query to the database for each $tagSelect item. If this array has 100 items you are going to execute 100 queries, which will be very slow.
Using @snapey suggestion you would execute just one query instead.
On Laravel docs there is a nice explanation of the N+1 query problem referred in @snapey answer:
reference: https://laravel.com/docs/9.x/eloquent-relationships#eager-loading
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