如何使用这样的php变量检查数据库？

如何使用这样的php变量检查数据库

我有

$check = "1234567890";

这是表：检查数据

 _________ ______________________________________________________________
|   id    |                         key_pass                             |
|_________|______________________________________________________________|
|____1____|_______________1234567890abcdefghij___________________________|
|____2____|_______________6545ryu76543werfdt54___________________________|
|____3____|_______________345jfuryt75yrhtufkgo___________________________|
|____4____|_______________weoiufoiweu9ew8ew8w8___________________________|
|____5____|_______________oi34ioruiofuefiusdfo___________________________|
|____6____|_______________iuyiuysdifuysfiuyfds___________________________|

我想这样检查一下

$sql = "SELECT * FROM check_data WHERE key_pass(first char to ten char) = '$check'";
$query = mysql_query($sql);
$result = mysql_fetch_array($query);
if($result)
  {echo "found";}
else
  {echo "not found";}

我该怎么做呢？

试试

LEFT(key_pass , 10);

像

您也可以像这样使用

$sql = "SELECT * FROM check_data WHERE SUBSTRING(key_pass ,1, 10) = '$check'";

---

查看MySQL手册，您正在寻找

子字符串

函数

$sql = "SELECT * FROM check_data WHERE SUBSTRING(key_pass, 1, 10) = '" . mysql_real_escape_string($check) . "';

您可以像这样使用

LEFT（）

函数：

ql = "SELECT * FROM check_data WHERE left(key_pass,10) = '$check'";

---

有一整套字符串函数是有用的。检查MySQL

您需要的功能如下：

$sql =  "SELECT * FROM check_data WHERE key_pass like ('$check%')";

你也可以这样做

$sql =  "SELECT * FROM check_data WHERE SUBSTR(key_pass,1,10) = '$check%'";

试试这个

    "SELECT * FROM check_data WHERE SUBSTR(key_pass,1,10) = ".$check

或

---

注意，PHP的mysql_uAPI已被弃用。子字符串从1开始。来源：将

%$check%”；

更改为

$check%”
$sql =  "SELECT * FROM check_data WHERE SUBSTR(key_pass,1,10) = '$check%'";

$sql = "SELECT * FROM check_data WHERE key_pass LIKE  % $check %";
$query = mysql_query($sql);
$result = mysql_fetch_array($query);
if($result)
  {echo "found";}
else
  {echo "not found";}

    "SELECT * FROM check_data WHERE SUBSTR(key_pass,1,10) = ".$check

    "SELECT * FROM check_data WHERE key_pass LIKE '".$check."%'"