<?php

$exportData = [
    'db0' => ['table0', 'table1'],
    'db1' => ['table0']
];

$user = 'test';
$password = 'test123';
$host = '127.0.0.1';
$path = '/tmp';

foreach ($exportData as $db => $tables) {
    foreach ($tables as $table) {
        $csvFile = $path . '/' . $db . '.' . $table . '.csv';

        $command = 'mysql -u ' . $user . ' -h' . $host . ' -p' . $password . ' -B -e "select * from ' . $db . '.' . $table . ' limit 10;"';
        //NOTE: change the separator as required; ',' is not suitable always
        $command .= '| sed "s/\'/\'/;s/\t/\",\"/g;s/^/\"/;s/$/\"/;s/\n//g" > ' . $csvFile;  //this regex is taken from stackoverflow; can't take its credit
        shell_exec($command);

        if (file_exists($csvFile)) {    //remove column header
            $command = "sed -i 1d $csvFile";
            shell_exec($command);
        }

        echo "Created $csvFile\n";
    }
}