多个内连接在php中不起作用

Question

所以我得到了这个完全在mysql phpmyadmin中工作的查询，但是当我在php文件中使用它时它不起作用。

SELECT * 
  FROM services_package 
  JOIN service_in_package 
    ON services_package.id = service_in_package.package_id 
  JOIN itv 
    ON service_in_package.service_id = itv.id 
  JOIN tv_genre 
    ON itv.tv_genre_id = tv_genre.id  
 WHERE services_package.id  = 25

任何想法为什么？

我已经多次尝试过，问题出现在这里：

INNER JOIN tv_genre ON itv.tv_genre_id = tv_genre.id

这是php代码：

    $sql = "
    SELECT * 
      FROM services_package 
      JOIN service_in_package 
        ON services_package.id = service_in_package.package_id 
      JOIN itv 
        ON service_in_package.service_id = itv.id 
      JOIN tv_genre 
        ON itv.tv_genre_id = tv_genre.id 
     WHERE services_package.id = 25
    "; 

$rows = array();

$result = $conn->query($sql);

if($result->num_rows > 0)
{
     while($r = mysqli_fetch_assoc($result)) {
    $rows[] = $r;

    }

echo json_encode($rows);

好的，所以我没有错误。 即使出现错误也是如此。 循环循环8次（这是正确的，因为它应该返回8行），但它没有输出。

它实际上在以下时间工作：

 INNER JOIN tv_genre ON itv.tv_genre_id = tv_genre.id

已移除。 我很混乱。

更新：我检查了phpmyadmin中的行，并注意到多行具有相同的名称“ID”，并认为它可能会在转换为JSON时产生冲突，因此我创建了一个新查询：

        SELECT itv.id AS channel_id, 
tv_genre.id AS genre_id, 
services_package.id AS service_package_id, 
itv.name AS channel_name, 
itv.descr AS channel_description, 
services_package.type AS channel_type, 
itv.number, itv.censored, 
itv.cmd AS channel_source, 
tv_genre.title AS genre_name, 
itv.logo
FROM services_package
JOIN service_in_package ON services_package.id = service_in_package.package_id
JOIN itv ON service_in_package.service_id = itv.id
JOIN tv_genre ON itv.tv_genre_id = tv_genre.id
WHERE services_package.id =25

这是在phpmyadmin工作，而不是在PHP文件中工作：/

var_dump结果（由于显而易见的原因改变了channel_source）：

array(11) { ["channel_id"]=> string(3) "846" ["genre_id"]=> string(2) "10" ["service_package_id"]=> string(2) "25" ["channel_name"]=> string(8) "HAC 2 HD" ["channel_description"]=> string(0) "" ["channel_type"]=> string(2) "tv" ["number"]=> string(1) "5" ["censored"]=> string(1) "0" ["channel_source"]=> string(45) "http://test.com" ["genre_name"]=> string(8) "Englisch" ["logo"]=> string(0) "" } array(11) { ["channel_id"]=> string(3) "845" ["genre_id"]=> string(2) "10" ["service_package_id"]=> string(2) "25" ["channel_name"]=> string(8) "HAC 1 HD" ["channel_description"]=> string(0) "" ["channel_type"]=> string(2) "tv" ["number"]=> string(1) "4" ["censored"]=> string(1) "0" ["channel_source"]=> string(44) "http://test.com" ["genre_name"]=> string(8) "Englisch" ["logo"]=> string(0) "" } array(11) { ["channel_id"]=> string(3) "831" ["genre_id"]=> string(2) "10" ["service_package_id"]=> string(2) "25" ["channel_name"]=> string(9) "HAC 3 HD " ["channel_description"]=> string(0) "" ["channel_type"]=> string(2) "tv" ["number"]=> string(1) "6" ["censored"]=> string(1) "0" ["channel_source"]=> string(45) "http://test.com" ["genre_name"]=> string(8) "Englisch" ["logo"]=> string(0) "" } array(11) { ["channel_id"]=> string(3) "829" ["genre_id"]=> string(2) "10" ["service_package_id"]=> string(2) "25" ["channel_name"]=> string(8) "HAC SD 3" ["channel_description"]=> string(0) "" ["channel_type"]=> string(2) "tv" ["number"]=> string(1) "3" ["censored"]=> string(1) "0" ["channel_source"]=> string(39) "http://test.com" ["genre_name"]=> string(8) "Englisch" ["logo"]=> string(0) "" } array(11) { ["channel_id"]=> string(3) "828" ["genre_id"]=> string(2) "10" ["service_package_id"]=> string(2) "25" ["channel_name"]=> string(8) "HAC SD 2" ["channel_description"]=> string(0) "" ["channel_type"]=> string(2) "tv" ["number"]=> string(1) "2" ["censored"]=> string(1) "0" ["channel_source"]=> string(39) "http://test.com" ["genre_name"]=> string(8) "Englisch" ["logo"]=> string(0) "" } array(11) { ["channel_id"]=> string(3) "814" ["genre_id"]=> string(2) "10" ["service_package_id"]=> string(2) "25" ["channel_name"]=> string(13) "Go To Luxe.TV" ["channel_description"]=> string(0) "" ["channel_type"]=> string(2) "tv" ["number"]=> string(2) "23" ["censored"]=> string(1) "0" ["channel_source"]=> string(41) "http://test.com" ["genre_name"]=> string(8) "Englisch" ["logo"]=> string(0) "" } array(11) { ["channel_id"]=> string(3) "808" ["genre_id"]=> string(1) "8" ["service_package_id"]=> string(2) "25" ["channel_name"]=> string(16) "Nature & Animaux" ["channel_description"]=> string(0) "" ["channel_type"]=> string(2) "tv" ["number"]=> string(2) "10" ["censored"]=> string(1) "0" ["channel_source"]=> string(36) "http://test.com" ["genre_name"]=> string(11) "Französisch" ["logo"]=> string(0) "" } array(11) { ["channel_id"]=> string(3) "807" ["genre_id"]=> string(1) "8" ["service_package_id"]=> string(2) "25" ["channel_name"]=> string(8) "HAC SD 1" ["channel_description"]=> string(0) "" ["channel_type"]=> string(2) "tv" ["number"]=> string(1) "1" ["censored"]=> string(1) "0" ["channel_source"]=> string(39) "http://test.com" ["genre_name"]=> string(11) "Französisch" ["logo"]=> string(0) "" }

我现在唯一能想到的就是在将结果转换为JSON时出现了问题

Answer 1

解决了！ 问题是我的mysql结果包含一些无法转换为JSON的字符使用此函数来修复它：

function utf8ize($mixed) {
    if (is_array($mixed)) {
        foreach ($mixed as $key => $value) {
            $mixed[$key] = utf8ize($value);
        }
    } else if (is_string ($mixed)) {
        return utf8_encode($mixed);
    }
    return $mixed;
}