使用INFORMATION_SCHEMA作为root，错误说它不存在？

Question

I'm using this php code to pull out the column headers in a test table I had created. However whenever I try to run the code it gives me this error: There was an error running the query [Table 'meta_test.information_schema' doesn't exist] from the information I've seen online it looks like my code should work, however this is the first time I've attempted something like this. Here is my code:

    $camp = $_POST['campaign'];
    $query = "SELECT COLUMN_NAME FROM INFORMATION_SCHEMA WHERE TABLE_NAME = '$camp'";

    try{
        if(!$result = $db->query($query)){
            die('There was an error running the query [' . $db->error . ']');
        }

        echo "<pre>";
        print_r($result);
        echo "</pre>";
    }catch(exception $e){
        echo $e;
    }

Answer 1

You need to specify the table name:

SELECT COLUMN_NAME
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = '$camp'