duanshan5259 2018-12-20 21:43
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我的SQL查询在PHP上是错误的,但适用于phpmyadmin [重复]

In my PHP code I try to get data from my database but I get

"Warning: mysqli_num_rows() expects parameter 1 to be mysqli_result, boolean given"

as an error.

I found on stackoverflow that this indicates that my SQL query is getting back false. if I copy my sql query into the phpmyadmin sql field everything works just fine.

I tried various different notations (giving 1 and true for the boolean "fährt")

$sql = "SELECT * FROM `$params` WHERE `fährt` = 1" ;
$result=mysqli_query($conn,$sql);
if(mysqli_num_rows($result) != 0){
    while($row = mysqli_fetch_array($result)){
        echo "<br>".$row[0]."-".$row[1]."-".$row[2]."-".$row[3]."-".$row[4]."-".$row[5];
    }
}else{
    echo "Fehler";
}

Expected: One entry from my database

Actual output: Warning: mysqli_num_rows() expects parameter 1 to be mysqli_result, boolean given

UPDATE

So I tried what was said in the comments but it for me it does not explain why it works when I copy it to phpmyadmin. Furthermore it does work without the where clause.

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  • dpkk8687 2018-12-20 22:03
    关注

    You need to use utf_8 for the MySQL Connection. See php.net/manual/de/mysqli.set-charset.php

    本回答被题主选为最佳回答 , 对您是否有帮助呢?
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