public function getStatement($usePlaceholders = true)
    {
        $statement = "";
        if ($this->isSelect()) {
            $statement = $this->getSelectStatement($usePlaceholders);
        } elseif ($this->isInsert()) {
            $statement = $this->getInsertStatement($usePlaceholders);
        } elseif ($this->isReplace()) {
            $statement = $this->getReplaceStatement($usePlaceholders);
        } elseif ($this->isUpdate()) {
            $statement = $this->getUpdateStatement($usePlaceholders);
        } elseif ($this->isDelete()) {
            $statement = $this->getDeleteStatement($usePlaceholders);
        }
        return $statement;
    }