使用php进行SQL搜索

Question

ok so I need to search a database for names of people that were born between two dates, the website asks the user to input a date in this format dd/mm/yyyy so i need to manipulate is so that it will work in my sql search. What I did was this

$date_1 = $_GET["date_1"];
$date_2 = $_GET["date_2"];

function reorderDate($date) { //30/11/1970
  $firstbrk = strpos($date, '/');
  $day = substr($date, 0, $firstbrk);
  $month = substr($date, $firstbrk + 1, -5);
  $year = substr($date, strlen($date) - 4);
  $corrDate = $year.
  "-".$day.
  "-".$month;
  return $corrDate;
}

echo $Cdate_1 = reorderDate($date_1);
echo $Cdate_2 = reorderDate($date_2);

$tablename = 'Cyclist';
$sql = "SELECT name, dob FROM Cyclist WHERE dob > ' . $Cdate_1 . ' AND dob < ' . $Cdate_2 . ';";

$res = & $db - > query($sql);
if (PEAR::isError($res)) {
  die($res - > getMessage());
}
echo "<br>";
echo $findings_numb = $res - > numRows();
while ($row = $res - > fetchRow()) {
  echo $row[0].
  "
";
}

I am not finding anything in the database, but if I use this line to search instead I find many results why?

$sql = "SELECT name, dob FROM Cyclist WHERE dob > '1970-30-11' AND dob < '1990-30-11';";

</div>

Answer 1

change

$sql = "SELECT name, dob FROM Cyclist WHERE dob > ' . $Cdate_1 . ' AND dob < ' . $Cdate_2 . ';";

to

$sql = "SELECT name, dob FROM Cyclist WHERE dob > '" . $Cdate_1 . "' AND dob < '" . $Cdate_2 . "';";