Question

Rhugveda desai->鲜花，莎丽服，普拉萨德

在我的应用程序中，我需要使用group by子句。但是我遇到语法错误。另外，如果我希望将数量列乘以数量以得到总数，该怎么办？我的表是inkind和inkind_items，其中inkind.id是inkind_items表中的外键，作为inkind_id。

SQLSTATE [42000]：语法错误或访问冲突：1055表达式＃11 SELECT列表的内容不在GROUP BY子句中，并且包含未聚合的列

我的inkind_items表格为inkind_items 我的inkind表是inkind 我的查询是：

$inkinds = DB::table('inkind')
     ->join('inkind_items', 'inkind.id', '=', 'inkind_items.inkind_id')
     ->select('inkind.*', 'inkind_items.*')
     ->groupBy('inkind_items.inkind_id')
     ->get();

Answer 1

尝试使用group_concat()

$inkinds = DB::table('inkind')
     ->join('inkind_items', 'inkind.id', '=', 'inkind_items.inkind_id')
     ->select('inkind.*', DB::raw('group_concat(inkind_items.name) as items'))
     ->groupBy('inkind_items.inkind_id')
     ->get();

这里我假设inkind的字段为name，而inkind_items的字段为items。

Answer 2

嗨。您今天早些时候问了另一个问题（关于在选中特定复选框时显示输入内容），但是在我提交答案之前将其删除了，所以我想我将答案粘贴在这里： < / p>

只是为了让您入门，这是有关如何使用的说明   addEventListener和createElement来达到您想要的结果。

在研究了代码和   附带的注释，请在上搜索尚不清楚的函数的名称   MDN。
  （例如，https://developer.mozilla.org/en-US/docs/Web/API/Document/getElementsByClassName。）

// Sets `box1` to refer to the first element on the page with the class "box".
const box1 = document.getElementsByClassName("box")[0];

// Sets `container` to be the element whose id attribute has the value "container".
//   (This is where our new input element, inside a new label element, will be added.)
const container = document.getElementById("container");

// Begins listening for clicks. From now on, whenever the user clicks anywhere
//   on the page, our listener will call the `noticeClick` function.
document.addEventListener("click", noticeClick);

function noticeClick(event){
  // Because this function's name is the second argument in 
  //   the call to `document.addEventListener`, above, it is
  //   automatically called every time a 'click' event happens on the 
  //   page (and it automatically receives that event as an argument.)
  // The "target" of the event is whatever the user clicked on.

  // So we set the variable `targ` to refer to this target, and we check whether:
  //   1) the clicked target is our checkbox,
  //   2) this click caused the checkbox to gain the "checked" attribute, and
  //   3) we have not already given the checkbox the "added" class
  const targ = event.target;
  if(targ.id == "box1" && targ.checked && !targ.classList.contains("added")){

  // If all three conditions are met, we...
    // ...set two variables, `label` and `val`
    const label = event.target.id;
    const val = event.target.value;

    // ...call the `createInput` function, passing these variables as its two arguments
    createInput(label, val);

    // ...give the checkbox the "added" class (so we can avoid accidentally adding it again)
    targ.classList.add("added");
  }
}

function createInput(newLabel, newValue){
  // When the user has checked our checkbox, the `noticeClick` function
  //   will call this function, which receives two arguments (which we can   
  //   see, by examining the `noticeClick` function, are two strings: the  
  //   `id` attribute of box1 and the `value` attribute of box1.)
  
  // We use `document.creatElement` to create an `input` element and a 
  //   `label` element, and `document.createTextNode` to set some text 
  //   to be used in the label (using the "newLabel" argument.)
  const myInput = document.createElement("input");
  const myLabel = document.createElement("label");
  const myLabelText = document.createTextNode(newLabel + " ");

  // We set our new `input` element's value using the "newValue" argument.
  myInput.value = newValue;

  // We use `appendChild` to put both the text and the input element
  //   inside the label, and to put the label inside `container`.
  myLabel.appendChild(myLabelText);
  myLabel.appendChild(myInput);
  container.appendChild(myLabel);
}


// This process can be applied to multiple checkboxes on the same page 
//   by adding a loop inside the `noticeClick` function, where the string
//   "box1" should be replaced with a variable that can refer to the id of a
//   different checkbox's `id` for each iteration of the loop.

<label>
  <input type="checkbox" id="box1" class="box" value="value1" />
  Label for box1
</label>
<hr />
<div id="container"></div>

Answer 3

您可以为此使用Laravel收集方法。

只需致电：

$inkinds->groupBy('inkind_id');

-> get（）之后的

。考虑到inkind_id是两个表的唯一列

如何在Laravel中使用按查询分组？

3 个答案: