QueryException, ErrorException and PDOException in Connection.php

问题

I would like to ask if you can help me with the errors I am encountering with my newly installed Laravel 5.4. Here is my blade template

home.blade.php

@extends('layouts.app') @section('content') <div class="container">
<div class="row">                           
            {{ App\StudentHistory::select(['date', 'student_id', 'grade'])
            ->where('subject', 'English')
            ->groupBy('student_id')
            ->orderBy('date','desc')
            ->first()
            ->get()}}
    </div>@endsection

Let me know what else you guys need, I'll update as you ask

回答1:

• You're trying to run a db query in your view, which is better suited in your controller.
• You can't use first() and get() together, use one.
• You're trying to output the query result directly, which is an object, which would throw an error even if your query was successful.

回答2:

You're doing xxx->first()->get() ...

You either call ->first() and get one object or do ->get() and get an array of objects

Reference https://laravel.com/docs/5.4/queries#retrieving-results

PS: I really can't see the advantages of doing those queries IN the view, that's missing the MVC objective of laravel.

来源：https://stackoverflow.com/questions/44043255/queryexception-errorexception-and-pdoexception-in-connection-php