check if the query results empty row mysqli

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一向
一向 2020-11-29 11:17

I am using this code, but I don\'t understand how to check if the query returns zero rows. How can I check that?

$results = $mysqli->query(\"SELECT ANNOUN         


        
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  • 2020-11-29 11:30

    You can use the num_rows on the dataset to check the number of rows returned. Example:

    $results = $mysqli->query("SELECT ANNOUNCE_NUMBER,ANNOUNCEMENTS,ANNOUNCE_TYPE,POST_DATE FROM home WHERE ANNOUNCE_NUMBER NOT LIKE $excludewelcome AND ANNOUNCE_NUMBER NOT LIKE $excludenews ORDER BY ANNOUNCE_NUMBER DESC LIMIT $position, $items_per_group");
    if ($results) { 
    
        if($results->num_rows === 0)
        {
            echo 'No results';
        }
        else
        {
            //output results from database
            while($obj = $results->fetch_object())
            {
                if($obj->ANNOUNCE_TYPE=='NEWSEVENTS')
                {
                    $realstring='News and Events';
                }
                else
                {
                $realstring='Welcome Note';
                }
    
                echo '<li id="item_'.$obj->ANNOUNCE_NUMBER.'"><strong>'.$realstring.'</strong></span>';
                echo '<br \>'; 
                echo '('.$obj->POST_DATE.' ) <span class="page_message">'.$obj->ANNOUNCEMENTS.'</span></li>';
            }
        }
    }
    
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  • 2020-11-29 11:40

    if array is look like this [null] or [null, null] or [null, null, null, ...]

    you can use implode:

    implode is use for convert array to string.

    $con = mysqli_connect("localhost","my_user","my_password","my_db");
    $result = mysqli_query($con,'Select * From table1');
    $row = mysqli_fetch_row($result);
    if(implode(null,$row) == null){
         //$row is empty
    }else{
         //$row has some value rather than null
    }
    
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