Give users completely safe sandboxed raw SQL reporting abilities

in-memory-sqlite-database.php

<?php

// Create in-memory SQLite database
$sqlite = new PDO('sqlite::memory:');

// Generate schema (for whatever tables you want)
$sqlite->prepare('CREATE TABLE users(id, family_id, first_name, last_name, email)')->execute();
$sqlite->prepare('CREATE TABLE families(id, name, phone, address)')->execute();

// Insert pre-defined data
foreach ($users as $user) {
    $sqlite->prepare('INSERT INTO users VALUES (:id, :family_id, :first_name, :last_name, :email)')->execute($user);
}

// Run custom database query
if (($query = $sqlite->prepare($request->query)) and $query->execute()) {
    // Handle results on success
    $results = $query->fetchAll(PDO::FETCH_ASSOC);
} else {
    // Get error on failure
    $error = $sqlite->errorInfo()[2];
}