dow98764 2016-09-01 11:26
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Mysql在开头添加值(concat),而不是在结尾?

Ok so when user like a comment, my script adds user name to comments table, likes row.

$ben = "Rose,";

mysql_query("UPDATE comments set likes = CONCAT(comments.likes, 
'".$ben."') WHERE id ='".$id."'") or die(mysql_error()); 

However, it adds at the end of the list. For example if likes row have these;

John,Mark,Mary,

after it adds, its

John,Mark,Mary,Rose,

But I want it to add to the beginning, like

Rose,John,Mark,Mary,

How can I do that ?

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1条回答 默认 最新

  • dpmwy80068 2016-09-01 11:31
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    change arguments order function_concat

    mysql_query("UPDATE comments set likes = CONCAT( 
    '".$ben."',comments.likes) WHERE id ='".$id."'") or die(mysql_error()); 
    

    With PDO:

    use \PDO as PDO;
    $PDO = new PDO('mysql:...');
    $Stm = $PDO->prepare("UPDATE comments set likes = CONCAT(?,comments.likes) WHERE id =?");
    $Stm->execute([$ben,$id]);
    
    本回答被题主选为最佳回答 , 对您是否有帮助呢?
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