如何检查用户是否在表上存在特定字母

Question

I am trying to check if a user has a specific letter on SQL table like:

I have SQL Table amx_amxadmins and columns id, username, access example:

amx_amxadmins:
--------------------------------------------------
| ID | USERNAME         | ACCESS                 |
--------------------------------------------------
| 1  | TEST1            | abcde                  |
--------------------------------------------------
| 2  | TEST2            | bcde                   |
--------------------------------------------------

The Flag A is for No Access .

So how do I check if user have in column access A or not?

For example:

<?php
    $check_user_flag = $mysqli->query("SELECT * FROM `$amxadmins` WHERE `username` = '$logged[username]' AND `access` LIKE 'a' ") or die(mysqli_error($mysqli));
    $checkUSRFLAG = $check_user_flag->fetch_assoc();
    if($checkUSRFLAG->num_rows >  "a"){
        echo "test";
    }
    else {
        echo "test2";
    }
?>
```

EDIT BY RyffLe

$query = "SELECT * FROM `$amxadmins` WHERE `username` = ?";
    $stmt = $mysqli->prepare($query);
    $stmt->bind_param('s', $param);
    $param = $logged['username'];
    $stmt->execute();
    $result = $stmt->bind_result();
    $stmt->close();

    $Permissions = $obj->access;

    if (strpos($Permissions, 'a')) {
       echo("An A has been found!");
    }
    else {
       echo("An A wasn't Found...");
    }

Answer 1

First of all wellcome on Stackoverflow Beytula Ibryam.

Thats Your table:

amx_amxadmins:
--------------------------------------------------
| ID | USERNAME         | ACCESS                 |
--------------------------------------------------
| 1  | TEST1            | abcde                  |
--------------------------------------------------
| 2  | TEST2            | bcde                   |
--------------------------------------------------

First of all you need to select all Data of the User you need to check from your Data:

$query = "SELECT * FROM `$amxadmins` WHERE `username` = ?";
$stmt = $mysqli->prepare($query);
$stmt->bind_param('s', $param);
$param = $logged[username];
$stmt->execute();
$result = $stmt->get_result();
$stmt->close();
$obj = $result->fetch_object();

Next is to get your access as string:

$Permissions = $obj->access;

Now we can go to check the access for your wanted literals:

if (strpos($Permissions, 'a')) {
   echo("An A has been found!");
}
else {
   echo("An A wasn't Found...");
}

Enjoy ;)

--- EDITS ---

    $query = "SELECT * FROM `?` WHERE `username` = ?";
    $stmt = $mysqli->prepare($query);
    $stmt->bind_param('ss', $amxadmins, $logged['username']);
    $stmt->execute();
    $result = $stmt->get_result();
    $stmt->close();
    $obj = $result->fetch_object();

    if($checkUSRFLAG->num_rows >  "a"){
        echo ("test");
    }
    else {
        echo("test2");
    }

If you don't have a MySQLi Connection File, add following lines in to your main file:

$mysqli = new mysqli('YOUR_DATABEAS_IP', 'YOUR_DATABEAS_USER', 'YOUR_DATABEAS_USER_PASSWORD', 'YOUR_DATABEAS_NAME', 'YOUR_DATABEAS_PORT');
        if($mysqli->connect_error) {
          exit('Error connecting to database'); //Should be a message a typical user could understand in production
        }
        mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);

Answer 2

It sounds like you're just looking for a wildcard search. Use the % character for that. So instead of this:

AND `access` LIKE 'a'

You'd have this:

AND `access` LIKE '%a%'