Question

我在mysql中有2个表;

items
categories

items在cat_id表

中有一个categories列指向其类别

我使用以下查询来获取项目和类别;

SELECT a.id, a.cat_id, a.rest_id, a.name, a.description, a.price, b.rest_id, b.name 
FROM items a, categories b 
WHERE a.cat_id = b.id AND b.rest_id = 1

我想使用ng-repeat来生成如下所示的列表;

Category A

Item (belongs to cat A)
Item (belongs to cat A)
Item (belongs to cat A)

Category B

Item (belongs to cat B)
Item (belongs to cat B)
Item (belongs to cat B)

如何使用ng-repeat

实现此目标

到目前为止，我有这个但是没有工作;

<div class="results-group" ng-repeat="(key, value) in fetchedData">
   <h3 style="text-align: left;"></h3>
    <ul>
     <li ng-repeat="data in value">
     </li>
    <ul>
</div>

感谢。

$query1 = "SELECT * FROM categories WHERE rest_id = $restaurant_id";
$select_all_cats = mysqli_query($connection, $query1);
$rows = $select_all_cats -> num_rows;

$arr1 = array();
$arr2 = array();
if($rows > 0) {
    while($rows = mysqli_fetch_assoc($select_all_cats)) { 
        $arr1[] = $rows;
        $cat_id = $rows['id']; 

        $query2 = "SELECT * FROM items WHERE cat_id = $cat_id";
        $select_all_items = mysqli_query($connection, $query2);
        $rowx = $select_all_items -> num_rows;
        if($rowx > 0) {
            while($rowx = mysqli_fetch_assoc($select_all_items)) {
                $arr2[] = $rowx;
            }
        }
    }
}

Answer 1

首先，您应该在PHP中删除嵌套查询。循环/嵌套查询是一种反模式，您应该学习识别并通常用适当的查询替换利用连接。

像这样的东西应该在PHP方面起作用：

// array to store results
$item_array = array();
$query = "SELECT
    cat.name AS cat_name,
    i.id AS id,
    i.name AS name,
    i.description AS description,
    i.price AS price
FROM categories AS cat
INNER JOIN items AS i
    ON cat.id = i.id
WHERE i.rest_id = ?
ORDER BY cat_name ASC";

$result = mysqli_query($connection, $query);
if($result) {
    while($row = mysqli_fetch_assoc($result)) {
        // read into 2D array
        $item_array[$row['cat_name']][] = $row;
    }
}

重要的是要注意我们在这里构建一个二维数组，类别名称是第一个维度。然后，您可以将此与ng-repeat一起使用，如下所示。请注意，我将在$item_array上面将itemData中的数据称为itemData。另请注意，{j}格式化时，itemData将采用对象的形式。 <div class="results-group" ng-repeat="(cat, items) in itemData"> <h3 style="text-align: left;">{{cat}}</h3> <ul> <li ng-repeat="item in items">  </li> <ul> </div>上的每个类别“属性”都将包含项目记录的数字索引数组。

SELECT to_date('36515', 'DDDYY') FROM DUAL

使用mysql进行ng-repeat分组

1 个答案: