【发布时间】：2021-06-23 23:20:10
【问题描述】：
我正在尝试从 MySql 表创建嵌套的 json 输出，并且正在努力解决出现的问题。
表格示例如下所示：
| id | county | county_code | region | region_code | entrants | population |
|---|---|---|---|---|---|---|
| 1 | Mombasa | KE.28 | Coast | KE.CO | 2526 | 1208333 |
| 2 | Kwale | KE.19 | Coast | KE.CO | 956 | 86682 |
| 18 | Nyandarua | KE.35 | Central | KE.CE | 1153 | 638289 |
| 19 | Nyeri | KE.36 | Central | KE.CE | 824 | 759164 |
| 23 | Turkana | KE-43 | Rift Valley | KE.RV | 183 | 926976 |
我正在尝试创建以下输出：
[
{
"id": "KE.CE",
"x": "Central",
"value": 368505,
"market_share": 28,
"total_share": 50,
"revenue": [
["Nyandarua",1153,0.181],
["Nyeri",824,0.109],
["Kirinyaga",395,0.065],
["Murang",487,0.046],
["Kiambu",2174,0.09]
]
},
{
"id": "KE.CO",
"x": "Coastal",
"value": 386097,
"market_share": 16,
"total_share": 20,
"revenue": [
["Mombasa",2526,0.209],
["Kwale",956,1.103],
["Kilifi",1260,0.087],
["Tana River",180,0.057],
["Lamu",71,0.493],
["Taita–Taveta",699,0.205]
]
},
{
"id": "KE.RV",
"x": "Rift Valley",
"value": 519026,
"market_share": 29,
"total_share": 47,
"revenue": [
["West Pokot",242,0.039],
["Samburu",64,0.021],
["Trans-Nzoia",1566,0.158],
["Uasin Gishu",1769,0.152],
["Elgeyo-Marakwet",243,0.535],
["Nandi",1929,0.218],
["Baringo",504,0.076],
["Laikipia",483,0.931],
["Nakuru",3482,0.161],
["Narok",843,0.073],
["Kajiado",881,0.079],
["Kericho",2661,0.295],
["Bomet",1005,0.115]
]
}
]
我创建的代码如下（注意我暂时使用Rand功能只是创建了一些虚拟数据）：
if (mysqli_connect_errno($conn)) {
echo "Failed to connect to DataBase: " . mysqli_connect_error();
}
else {
/* Declare arrays */
$output_array =array();
$region_array = array();
$county_array = array();
$fetch_region = mysqli_query($conn, "SELECT distinct region_code as id, region as x, sum(entrants) as value,
FLOOR(RAND()*(60-10+1))+20 as market_share,
FLOOR(RAND()*(70-50+1))+20 as total_share
from reporting_summary_county
group by region_code") or die(mysqli_error($conn));
while ($row_region = mysqli_fetch_assoc($fetch_region)) {
$region_array['id'] = $row_region['id'];
$region_array['x'] = $row_region['x'];
$region_array['value'] = $row_region['value'];
$region_array['market_share'] = $row_region['market_share'];
$region_array['total_share'] = $row_region['total_share'];
$region_array['revenue'] = array();
$fetch_county = mysqli_query($conn,"SELECT county, sum(entrants) as v1, round((sum(entrants)/sum(population))*100,3) as v2
from reporting_summary_county
where region_code = ".$row_region['id']."
group by county"
) or die(mysqli_error($conn));
while ($row_county = mysqli_fetch_assoc($fetch_county)) {
$county_array['county']=$row_county['county'];
$county_array['v1']=$row_county['v1'];
$county_array['v2']=$row_county['v2'];
array_push($region_array['revenue'],$county_array);
}
array_push($output_array,$region_array);
}
$jsonData = json_encode($output_array, JSON_PRETTY_PRINT);
echo $jsonData;
}
在运行代码时，会输出以下消息：
Unknown column 'KE.CE' in 'where clause'
我相信问题出在这行：
where region_code = ".$row_region['id']."
我尝试了不同的输出选项，并尝试不转义变量，但没有成功。
有趣的是，当我用硬编码区域替换 $row_region 变量时，它会返回预期的输出，但是，对于硬编码的区域，内部收入数据会重复。
输出还突出了另一个问题，即字段名称也显示在收入部分输出中，我只想查看值。我需要进一步调查。
where region_code = 'KE.CE'
此更改的输出：
[ { "id": "KE.CE", "x": "Central", "value": "5033", "market_share": "51", "total_share": "20", "revenue": [ { "county": "Kiambu", "v1": "2174", "v2": "0.090" }, { "county": "Kirinyaga", "v1": "395", "v2": "0.065" }, { "county": "Muranga", "v1": "487", "v2": "0.046" }, { "county": "Nyandarua", "v1": "1153", "v2": "0.181" }, { "county": "Nyeri", "v1": "824", "v2": "0.109" } ] }, { "id": "KE.CO", "x": "Coast", "value": "5692", "market_share": "26", "total_share": "24", "revenue": [ { "county": "Kiambu", "v1": "2174", "v2": "0.090" }, { "county": "Kirinyaga", "v1": "395", "v2": "0.065" }, { "county": "Muranga", "v1": "487", "v2": "0.046" }, { "county": "Nyandarua", "v1": "1153", "v2": "0.181" }, { "county": "Nyeri", "v1": "824", "v2": "0.109" } ] }, { "id": "KE.NA", "x": "Nairobi(Province)", "value": "10870", "market_share": "25", "total_share": "38", "revenue": [ { "county": "Kiambu", "v1": "2174", "v2": "0.090" }, { "county": "Kirinyaga", "v1": "395", "v2": "0.065" }, { "county": "Muranga", "v1": "487", "v2": "0.046" }, { "county": "Nyandarua", "v1": "1153", "v2": "0.181" }, { "county": "Nyeri", "v1": "824", "v2": "0.109" } ] }, { "id": "KE.NE", "x": "North Eastern", "value": "4726", "market_share": "59", "total_share": "23", "revenue": [ { "county": "Kiambu", "v1": "2174", "v2": "0.090" }, { "county": "Kirinyaga", "v1": "395", "v2": "0.065" }, { "county": "Muranga", "v1": "487", "v2": "0.046" }, { "county": "Nyandarua", "v1": "1153", "v2": "0.181" }, { "county": "Nyeri", "v1": "824", "v2": "0.109" } ] }, { "id": "KE.NR", "x": "Eastern", "value": "5467", "market_share": "45", "total_share": "20", "revenue": [ { "county": "Kiambu", "v1": "2174", "v2": "0.090" }, { "county": "Kirinyaga", "v1": "395", "v2": "0.065" }, { "county": "Muranga", "v1": "487", "v2": "0.046" }, { "county": "Nyandarua", "v1": "1153", "v2": "0.181" }, { "county": "Nyeri", "v1": "824", "v2": "0.109" } ] }, { "id": "KE.NY", "x": "Nyanza", "value": "12130", "market_share": "63", "total_share": "31", "revenue": [ { "county": "Kiambu", "v1": "2174", "v2": "0.090" }, { "county": "Kirinyaga", "v1": "395", "v2": "0.065" }, { "county": "Muranga", "v1": "487", "v2": "0.046" }, { "county": "Nyandarua", "v1": "1153", "v2": "0.181" }, { "county": "Nyeri", "v1": "824", "v2": "0.109" } ] }, { "id": "KE.RV", "x": "Rift Valley", "value": "15855", "market_share": "30", "total_share": "20", "revenue": [ { "county": "Kiambu", "v1": "2174", "v2": "0.090" }, { "county": "Kirinyaga", "v1": "395", "v2": "0.065" }, { "county": "Muranga", "v1": "487", "v2": "0.046" }, { "county": "Nyandarua", "v1": "1153", "v2": "0.181" }, { "county": "Nyeri", "v1": "824", "v2": "0.109" } ] }, { "id": "KE.WE", "x": "Western", "value": "5163", "market_share": "43", "total_share": "25", "revenue": [ { "county": "Kiambu", "v1": "2174", "v2": "0.090" }, { "county": "Kirinyaga", "v1": "395", "v2": "0.065" }, { "county": "Muranga", "v1": "487", "v2": "0.046" }, { "county": "Nyandarua", "v1": "1153", "v2": "0.181" }, { "county": "Nyeri", "v1": "824", "v2": "0.109" } ] } ]
更新： 如果我将代码更改为使用连接字符串：
where region_code = '".$row_region['id']."'
输出返回一个空白屏幕。
我还修改了代码以使用绑定变量，这将返回相同的空白输出。
$query = "SELECT county, sum(entrants) as v1, round((sum(entrants)/sum(population))*100,3) as v2
from reporting_summary_county
where region_code =?
group by county";
$sql = $conn->prepare($query);
$sql->bind_param("s", $row_region['id']);
if (!$sql->execute()) {
echo "Error: " . $query . "<br>" . $sql->error;
}
$fetch_county = $sql->get_result();
例如，如果我在 bind_param 部分出错并将其更改为不存在的内容：
$sql->bind_param("s", $test['id']);
这会返回一个输出，减去收入部分。
[ { "id": "KE.CE", "x": "Central", "value": "5033", "market_share": "44", "total_share": "37", "revenue": [] }, { "id": "KE.CO", "x": "Coast", "value": "5692", "market_share": "65", "total_share": "30", "revenue": [] }, { "id": "KE.NA", "x": "Nairobi(Province)", "value": "10870", "market_share": "45", "total_share": "25", "revenue": [] }, { "id": "KE.NE", "x": "North Eastern", "value": "4726", "market_share": "59", "total_share": "27", "revenue": [] }, { "id": "KE.NR", "x": "Eastern", "value": "5467", "market_share": "50", "total_share": "37", "revenue": [] }, { "id": "KE.NY", "x": "Nyanza", "value": "12130", "market_share": "41", "total_share": "35", "revenue": [] }, { "id": "KE.RV", "x": "Rift Valley", "value": "15855", "market_share": "52", "total_share": "36", "revenue": [] }, { "id": "KE.WE", "x": "Western", "value": "5163", "market_share": "68", "total_share": "29", "revenue": [] } ]
这似乎在我看来，$query 部分的代码中存在问题。 我已经看这个太久了，显然看不到树木的树木。
任何帮助或建议将不胜感激。
【问题讨论】：
-
没有数据返回的问题归结为县的拼写。我通过使用
var_dump($county_array);找到了这个