比较多维数组中的两个 DATETIME 字段和 return 一个值或索引

Compare two DATETIME fields from multidimensional array and return a value or index

我有一个用户table。我正在查看每行 2 DATETIME。我将查看 $lastLog 日期和 $lastReceived(最后收到的线索)并确定哪个更新并成为他们的 $eligibleTime。然后我们将寻找最老的 $eligibleTime 到 select 哪个用户应该获得潜在客户。我正在筛选用户,以确保他们在潜在客户所处的适当状态下获得许可,并且还确保他们没有达到每日配额。

我在想,也许我错误地构建了多维数组,应该将所有 $lastLog 日期和 $lastReceived 日期分组到它们自己的数组中,并且 运行 max($array) 或类似的内容。

我怎么看这个?我使用以下方法构建了一个多维数组:

    $sql = "SELECT `lastLog`,`firstName`,`lastReceived` FROM customers";
    $sql = mysqli_query($conn,$sql);
    $result = array();
    while($line = mysqli_fetch_assoc($sql)){
      $result[] = $line;
    }

它正在返回以下数据:

> Array ( [0] => Array ( [lastLog] => 2015-06-12 02:00:00 [firstName] => Nathaniel [lastReceived] => 2015-06-12 05:16:10 ) [1] => Array ( [lastLog] => 2015-06-12 01:00:00 [firstName] => Ignacio [lastReceived] => 2015-06-01 10:00:00 ) [2] => Array ( [lastLog] => 2015-06-12 00:00:00 [firstName] => James [lastReceived] => 2015-06-08 00:00:00 ) [3] => Array ( [lastLog] => 2015-06-12 04:00:00 [firstName] => Robert [lastReceived] => 2015-06-10 00:00:00 ) ) 

谢谢你,内特

感谢 Marc B,这个问题得到了解决。

$sql = mysqli_query($conn,
   "SELECT firstName, greatest(lastLog, lastReceived) AS eligibleTime 
    FROM customers 
    ORDER BY eligibleTime DESC
    LIMIT 1");
$result = mysqli_fetch_assoc($sql);
print_r($result);