This article demonstrate how we can export records from MySQL Table to a CSV file. fputcsv() is a buit in function of PHP which takes an array and a file pointer as parameters which convert the array data into CSV format and writes it to the file.

In the below code first we create a file pointer using fopen() and set the value for Content-type and Content-Disposition in header(). And then, pass file pointer and array of database records into fputcsv() to generate CSV file.

 <?php
    $host = 'hostname';
    $user = 'username';
    $password = 'password';
    $database = 'database_name';
    $table = 'table_name';

    //Connect to database
    $con = mysqli_connect($host, $user, $password, $database);

    $filename = "sample.csv";
    $file = fopen('php://output', 'w');

    //To fetch column names of table
    $query = "SELECT COLUMN_NAME FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_SCHEMA='".$database."' AND TABLE_NAME='".$table."'";
    $result = mysqli_query($con, $query);
    while ($res = mysqli_fetch_row($result)) {
        $header[] = $res[0];
    }

    //Generate CSV file    
    header('Content-type: application/csv');
    header('Content-Disposition: attachment; filename='.$filename);
    fputcsv($file, $header);

    //To fetch records from table        
    $query = "SELECT * FROM $table";
    $result = mysqli_query($con, $query);
    while($data = mysqli_fetch_row($result)) {
        fputcsv($file, $data);
    }
    fclose($file);
    ?>