php - 从 php 中的查询返回结果

Question

我得到了这样的查询结果:(book_id, 年)

37 2014 
37 2012
35 2013
35 2012
35 2011

我想这样回应

book id is 37 from 2014
editions available are 2014 and 2012 

Answer 1

一种方法是将它们分组在一个容器中，然后只需使用 min 和 max:

// grouping
$container = array();
while($row = your_fetch_assoc($result_set)) {
    $container[$row['book_id']][] = $row['yr'];
}

// then comes the presentation
foreach($container as $book_id => $year) {
    $to = max($year);
    $from = min($year);
    echo "
        book id is {$book_id} <br/>
        editions available are {$to} and {$from} <br/><br/>
    ";
}