ActiveRecord\Table::create_joins PHP Method

    public function create_joins($joins)
    {
        if (!is_array($joins)) {
            return $joins;
        }
        $ret = $space = '';
        $existing_tables = array();
        foreach ($joins as $value) {
            $ret .= $space;
            if (stripos($value, 'JOIN ') === false) {
                if (array_key_exists($value, $this->relationships)) {
                    $rel = $this->get_relationship($value);
                    // if there is more than 1 join for a given table we need to alias the table names
                    if (array_key_exists($rel->class_name, $existing_tables)) {
                        $alias = $value;
                        $existing_tables[$rel->class_name]++;
                    } else {
                        $existing_tables[$rel->class_name] = true;
                        $alias = null;
                    }
                    $ret .= $rel->construct_inner_join_sql($this, false, $alias);
                } else {
                    throw new RelationshipException("Relationship named {$value} has not been declared for class: {$this->class->getName()}");
                }
            } else {
                $ret .= $value;
            }
            $space = ' ';
        }
        return $ret;
    }