Helper para PDO

DB.php

<?php

class DB
{
    /**
     * @var \PDO
     */
    private $pdo;

    public function __construct(string $dsn, string $username, string $passwd, array $options = [])
    {
        $this->pdo = new \PDO($dsn, $username, $passwd, $options);
    }

    public function exec(string $sql, array $params = []) : int
    {
        return $this->prepare($sql, $params)
            ->rowCount();
    }

    private function prepare(string $sql, array $params) : \PDOStatement
    {
        $stmt = $this->pdo->prepare($sql);
        if (!$stmt) {
            throw new \PDOException('Falha ao preparar query');
        }

        foreach ($params as $key => $value) {
            $stmt->bindValue($key, $value);
        }

        if (!$stmt->execute()) {
            throw new \PDOException('Falha ao executar query');
        }

        return $stmt;
    }

    public function queryAll(string $sql, array $params = []) : array
    {
        return $this->prepare($sql, $params)
            ->fetchAll(\PDO::FETCH_ASSOC);
    }

    public function queryOne(string $sql, array $params = [])
    {
        $rows = $this->prepare($sql, $params)
            ->fetchAll(\PDO::FETCH_NUM);

        if (!count($rows)) {
            return false;
        }

        return current(current($rows));
    }

    public function queryRow(string $sql, array $params = []) : array
    {
        $rows = $this->prepare($sql, $params)
            ->fetchAll(\PDO::FETCH_ASSOC);

        return current($rows);
    }

    public function queryColumn(string $sql, array $params = [], int $column = 0) : array
    {
        $rows = $this->prepare($sql, $params)
            ->fetchAll(\PDO::FETCH_NUM);

        return array_column($rows, $column);
    }

    public function transaction($closure) : bool
    {
        $this->pdo->beginTransaction();

        try {
            $closure($this);
            return $this->pdo->commit();
        } catch (\Exception $e) {
            $this->pdo->rollBack();
            throw $e;
        }
    }

    public function beginTransaction() : bool
    {
        return $this->pdo->beginTransaction();
    }

    public function commit() : bool
    {
        $this->pdo->commit();
    }

    public function rollBack() : bool
    {
        $this->pdo->rollBack();
    }

    public function getLastID($name = null)
    {
        return $this->pdo->lastInsertId($name);
    }
}