private function makeExpressions($conditions, $alias = self::DEFAULT_TABLE_ALIAS)
    {
        $expressions = [];
        foreach ($conditions as $attr) {
            $field = $attr['field'];
            if (strpos($field, '.') > 0) {
                //monta os joins
                $newAliasField = $this->associationQueryFields($field);
                $alias = $newAliasField['alias'];
                $field = $newAliasField['field'];
            }
            $expressions[] = $this->makeExpression($field, $attr['operation'], $attr['value'], $alias);
        }

        return $expressions;
    }