SQL喜欢用变量查询吗？

Question

I have this function:

function word($arg){

    echo ''.$arg.'';
    //echoes test

    require ('config.php');

    $requestSQL = mysql_query("SELECT * FROM db where eng LIKE '%$arg%' order by id ASC LIMIT 10", $connection);
    while ($row = mysql_fetch_array($requestSQL))
    {
        echo ''.$row['id'].': '.$row['eng'].'<br>';
    }

}

Gets triggered by:

$number = $explode[1];
word($number);

---

But doesn't echo values from the database, nothing at all. If I echo $arg (in the function), it shows the value. If I replace in my sql query: '%$arg%' with '%test%', it echoes the correct value.

Is the '%$arg%' syntax wrong?

Answer 1

您应该使用适当的连接器

"SELECT * FROM db where eng LIKE concat('%', '$arg', '%') order by id ASC LIMIT 10"

Answer 2

It's pretty simple, all you do is: LIKE %{$arg}% . Because I am assuming that $arg is a text value. If a variable is a text value then you must do this to keep it working. You wrap text variables in {} .

Also, never . . . EVER use mysql_* , you should move to mysqli_* or PDO/OOP. It's just good practice.

Update

---

You can't use variables within mysql_query("", $connection) quotes. Instead, do this:

$query = "SELECT * FROM db WHERE eng LIKE '%{$arg}%' ORDER BY id ASC LIMIT 10";

// then use this variable as a replacement for the quotes in the mysql_query().    

$set = mysql_query($query, $connection); // like so . . .

// mysql_fetch_assoc() is the same as mysql_fetch_array().

while($row = mysql_fetch_assoc($set)) {
  echo "".$row['id'].": ".$row['eng']."<br>";
}

Answer 3

I'm so stupid, actually $explode[1]; was returning the correct value but had a blank line in the source code. So I had to use trim and now it works.