php mysql如何在datewise中获取结果行

Question

I need to get the result rows as date wise for example, i have

prs_id date                desc
1      2015-07-10          Test data1
2      2015-07-10          Test data2
3      2015-07-11          Test data3

med_id prs_id drug                dosage
1      1      Pracetamol          3
2      1      calpol              4
3      2      crocin              5
4      3      xxxxxx              8

i need to form the array and need to display like the below

2015-07-10
     1 Test data1

          1      1      Pracetamol          3
          2      1      calpol              4

     2 Test data2
          3      3      crocin              5

2015-07-11
     3 Test data3
          4      3      xxxxxx              8

I tried the following code

$sql = "SELECT * from prescriptions";
$result = $conn->query($sql);

if ($result->num_rows > 0) {
    // output data of each row
    while($row = $result->fetch_assoc()) {

                $answer[$row['prs_created_date']][] = $row;


    }
}

below code simply prints the array, with prescription data as the key, thanks Marc B for this. But i need to print as the expected table, how can i do that.

echo '<pre>';
print_r($answer);

Answer 1

Sort your results using order by date_col and then in php use below logic to display your results

$sql = "SELECT * from prescriptions order by date_col";
$result = $conn->query($sql);
$date= false;
if ($result->num_rows > 0) {

    while($row = $result->fetch_assoc()) {
        if ($date != $row['date'])
        {
        echo '<h1>'.$row['date'].'</h1>';
        $date = $row['date'];
        }
        echo '<p>' . $row['id'] . '</p>';
        echo '<p>' . $row['desc'] . '</p>';
        .
        .
        .
    }

}