将varchar中的日期与mysql和php进行比较

Question

我正在尝试比较名为“fecha_registro”的列中的两个日期，此列是varchar（100），我正在尝试将他与此日期代码进行比较：

<?php

$host = "localhost";
$user = "root";
$pass = "";
$db   = "gimnasio";

mysql_connect($host, $user, $pass);
mysql_select_db($db);

$from = "2010-02-06";
$to = "2015-11-08";

$consulta = mysql_query("SELECT id_cliente FROM clientes WHERE fecha_registro BETWEEN '$from' AND '$to'");
$cantidad = mysql_num_rows($consulta);

echo $cantidad;

?>

问题是，当满足该模式的多个记录

时，您永远找不到任何记录

“clients”表的结构如下：

这样的记录：

拜托，我解决了这个问题？

Answer 1

试试这个

 SELECT id_cliente FROM clientes WHERE  
 DATE_FORMAT(STR_TO_DATE(fecha_registro, '%Y-%c-%e'), '%Y-%m-%d')
 BETWEEN '$from' AND '$to'

Answer 2

你可以这样试试

SELECT id_cliente FROM clientes WHERE  
STR_TO_DATE(fecha_registro, '%Y-%m-%d')
BETWEEN '$from' AND '$to'