使用 PHP 和 MySQL 查询为一系列数据创建 JSON

Question

我正在尝试使用 JSON 数据创建条形图，并且需要将格式更改为月份系列，但我对如何做到这一点感到困惑。请帮助我如何解决这个问题。

当前 JSON 数据：

{ “数据”：[

{

"name": "一月",

“设施”：“讨论室”，

“价值”：22

},

{

"name": "一月",

“设施”：“Carrel Room”，

“价值”：102

},

{

"name": "一月",

“设施”：“储物柜”，

“值”：5

},

{

"name": "二月",

“设施”：“讨论室”，

“价值”：86

},

{

"name": "二月",

“设施”：“Carrel Room”，

“价值”：155

},

{

“名称”：“Mac”，

“设施”：“Carrel Room”，

“价值”：224

},

{

“名称”：“Mac”，

“设施”：“储物柜”，

“值”：3

},

]

}

所需的 JSON 数据：

{ “数据”：[

{

"name": "一月",

“系列”：[

{ "name":"讨论室","value": 22},

{ "name": "Carrel Room", "value": 102},

{“名称”：“储物柜”，“价值”：5}，

]

"name": "二月",

“系列”：[

{ "name":"讨论室","value": 86},

{ "name": "Carrel Room", "value": 155},

{“名称”：“储物柜”，“价值”：0}，

]

"name": "三月",

“系列”：[

{ "name":"讨论室","value": 0},

{ "name": "Carrel Room", "value": 224},

{“名称”：“储物柜”，“价值”：3}，

]

]

}

我的代码：

$db = mysqli_connect($host, $user, $pass, $database) or die("you did not connect");

    header('Access-Control-Allow-Origin: *');
    header("Access-Control-Allow-Credentials: true");
    header('Access-Control-Allow-Methods: GET');
    header('Access-Control-Max-Age: 1000');
    header('Access-Control-Allow-Headers: Origin, Content-Type');

$facility =($_GET['year']);

$query = "select monthname(datetime) as 'name',
        case 
            when all_items.itype = '127' then 'Discussion Room'
            when all_items.itype = '126' then 'Carrel Room'
            when all_items.itype = '121' then 'Locker'
            else '0' 
        end as 'facility',
        count(*) AS 'value'

        from statistics 
        left join (
            select itemnumber, itype from deleteditems
            union
            select itemnumber, itype from items 
            ) as all_items USING (itemnumber)

        where all_items.itype in (127, 126, 121) and
        statistics.type = 'issue' and
        year(statistics.datetime) = '$facility' 

        group by month(datetime), all_items.itype desc";

$result = mysqli_query($db, $query)or die(mysqli_error());

$response = array();

$posts = array();

while($row=$result->fetch_assoc()) 
{ 
$month=$row['name'];
$facility=$row['facility'];
$value=$row['value'];

$posts[] = array('name'=> $month, 'facility'=> $facility, 'value'=> $value); 
}

$response['data'] = $posts;

header('Content-Type: application/json');
echo json_encode($response, JSON_NUMERIC_CHECK | JSON_PRETTY_PRINT);

Answer 1

您应该更改查询数据库的方式。您应该使用准备好的语句，而不是在查询中注入字符串。这使您容易受到 sql 注入的影响。

Read more about prepared statements.

回到问题：

对于发现的每个月，您需要创建一个数组，其中包含一个系列数组。检查月份数组是否存在，如果它不创建它并创建系列数组。然后创建一个包含系列数据的数组，并将其中的系列数据推送到该月的系列数组中。

查看代码要容易得多。我也添加了 cmets。

$result = mysqli_query($db, $query)or die(mysqli_error());

$response = array();

$posts = array();

while($row=$result->fetch_assoc()) 
{
    $month=$row['name'];

    if(!isset($posts[$month])){// Check to see if the month array exists
    //if it doesn't create it
        $posts[$month] = array();

        //create the series array so data can be pushed to it
        $posts[$month]["series"] = array();
    }

    //check to see if it is null and if it is make it 0
    if(is_null($row['value'])){
        $row['value'] =0;
    }

    //put the series data in the correct format with correct names
    $series_array = array(
        "name" => $row['facility'],
        "value" => $row['value']
    );

    //push the series data into the months series array
    array_push($posts[$month]["series"],$series_array);
}
// put months and series together 
$new_posts=array();
foreach($posts as $month_name => $data){
    array_push($new_posts, array("name"=> $month_name, "series"=> $data['series'] ));
}

$posts = $new_posts;
$response['data'] = array($posts);

header('Content-Type: application/json');
echo json_encode($response, JSON_NUMERIC_CHECK | JSON_PRETTY_PRINT);

Answer 2

这是您需要的代码

$result = mysqli_query($db, $query)or die(mysqli_error($db));
$response = array();
$posts = array();
while($row=$result->fetch_assoc()){
    $month = $row['name'];
    $value = $row['value'];
    if(empty($value)){
        $value = 0;
    }
    $series = array(
        "name"  => $row['facility'],
        "value" => $value 
    );
    $found_key = array_search($month, array_column($posts, 'name'));// check if month value exist in name key 
    if(!$found_key){//if not found
        $found_key = sizeof($posts);// get the size of array which will be 1 more then last index of array 
    }
    $posts[$found_key]['name']  = $month;// this add name of month 
    if(!isset($posts[$found_key]['series'])){ // check if series is set
       $posts[$found_key]['series'] = array();// or set it
    }
    $posts[$found_key]['series'][] = $series; //assign the series array
}
$response['data'] = $posts;
header('Content-Type: application/json');
echo json_encode($response, JSON_NUMERIC_CHECK | JSON_PRETTY_PRINT);