framework/db/conditions/InConditionBuilder.php
protected function buildSubqueryInCondition($operator, $columns, $values, &$params)
    {
        $sql = $this->queryBuilder->buildExpression($values, $params);

        if (is_array($columns)) {
            foreach ($columns as $i => $col) {
                if (strpos($col, '(') === false) {
                    $columns[$i] = $this->queryBuilder->db->quoteColumnName($col);
                }
            }

            return '(' . implode(', ', $columns) . ") $operator $sql";
        }

        if (strpos($columns, '(') === false) {
            $columns = $this->queryBuilder->db->quoteColumnName($columns);
        }

        return "$columns $operator $sql";
    }
protected function buildSubqueryInCondition($operator, $columns, $values, &$params)
    {
        $sql = $this->queryBuilder->buildExpression($values, $params);

        if (is_array($columns)) {
            foreach ($columns as $i => $col) {
                if (strpos($col, '(') === false) {
                    $columns[$i] = $this->queryBuilder->db->quoteColumnName($col);
                }
            }

            return '(' . implode(', ', $columns) . ") $operator $sql";
        }

        if (strpos($columns, '(') === false) {
            $columns = $this->queryBuilder->db->quoteColumnName($columns);
        }

        return "$columns $operator $sql";
    }
Builds SQL for IN condition.

@param string $operator
@param array|string $columns
@param Query $values
@param array $params
@return string SQL