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Question

I am having an issue with my MySQL query am not sure where the error is exactly.
Have some data in MySQL database, when I try to export some selected data as Excel format it works but it dublicates the data.

This is my database and the table name is tbl_employee

Mysql database

This is the output of the selected data on webpage
Webpage data

Below is the code although I saw this online and try to modify it by adding a checkbox to select some desire data

index.php
   <?php
    $connect = mysqli_connect("localhost", "root", "", "export");
    $query = "SELECT * FROM tbl_employee ORDER BY id desc";
    $result = mysqli_query($connect, $query);
    ?>
    <!DOCTYPE html>
    <html>

    <head>
        <title>Webslesson Tutorial | Export Mysql Table Data to CSV file in PHP</title>
        <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.1.0/jquery.min.js"></script>
        <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css" />
        <script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
    </head>

    <body>
        <br /><br />
        <div class="container" style="width:900px;">
            <h2 align="center">Export Mysql Table Data to CSV file in PHP</h2>
            <h3 align="center">Employee Data</h3>
            <br />
            <form method="post" action="export.php" align="center">
                <input type="submit" name="export" value="CSV Export" class="btn btn-success" />
                <br />
                <div class="table-responsive" id="employee_table">
                    <table class="table table-bordered">
                        <tr>
                            <th width="5%">ID</th>
                            <th width="5%">Select</th>
                            <th width="25%">Name</th>
                            <th width="35%">Address</th>
                            <th width="10%">Gender</th>
                            <th width="20%">Designation</th>
                            <th width="5%">Age</th>
                            </tr>
                            <?php
                            while ($row = mysqli_fetch_array($result)) {
                            ?>
                            <tr>
                                <td><?php echo $row["Id"]; ?></td>
                                <td><input type="checkbox" id="vehicle1" name="txtSelectedId[]" value="<?php echo $row["Id"]; ?>"></td>
                                <td><?php echo $row["col_name"]; ?></td>
                                <td><?php echo $row["col_address"]; ?></td>
                                <td><?php echo $row["col_gender"]; ?></td>
                                <td><?php echo $row["col_designation"]; ?></td>
                                <td><?php echo $row["col_age"]; ?></td>
                                </tr>
                        <?php
                        }
                        ?>
                    </table>
                </div>
            </form>
        </div>
    </body>

    </html>


export.php
    if (isset($_POST["export"])) {
        $connect = mysqli_connect("localhost", "root", "", "export");
        header('Content-Type: text/csv; charset=utf-8');
        header('Content-Disposition: attachment; filename=data.csv');
        $output = fopen("php://output", "w");
        fputcsv($output, array('Name', 'Address', 'Gender', 'Designation', 'Age'));

        foreach ($_POST["txtSelectedId"] as $selectedbox) {
            $query = "SELECT * from tbl_employee WHERE id = '$selectedbox' ORDER BY id ";
            $result = mysqli_query($connect, $query);
            $display = mysqli_fetch_array($result);
            fputcsv($output, $display);
        }
    }
    fclose($output);

This is what I get when I open the downloaded file in Excel
The downloaed file result

As you can see it suppose to be single data entry not double please I want the data to display in the same column
I want it to be like this

My desired result

And also I also like to export this same data with checkbox as PDF and download too.
Please anyone help

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Danh mục

Export some selected data from MySQL database without dublicate