**Usage**
Postgres, MySQL, and Oracle support the expression `LEFT JOIN ... ON 1 = 1`, but ClickHouse does not.

It may be possible to replace `LEFT JOIN ... ON 1 = 1` with `CROSS JOIN`, but I want to use the query in the same form for lots of databases.

Please support the expression `LEFT JOIN ... ON 1 = 1`.


**Detailed SQL**
```SQL
CREATE TABLE test
(
    `name` Nullable(String),
    `id` int
)
ENGINE = Log();

insert into test values ('a', 1) ('b', 2) (null, 3);

select * from test t1 left join (select * from test ) t2 on 1 = 1   
-- DB::Exception: Not equi-join ON expression: 1 = 1. No columns in one of equality side.: While processing 1 = 1.
```

{
    if (hasUsing())
        return 0;
    size_t count = 0;
    for (const auto & clause : clauses)
        count += std::count(clause.key_names_right.begin(), clause.key_names_right.end(), name);
    return count;
}
void TableJoin::deduplicateAndQualifyColumnNames(const NameSet & left_table_columns, const String & right_table_prefix)
{
    NameSet joined_columns;
    NamesAndTypesList dedup_columns;
    for (auto & column : columns_from_joined_table)
    {
        if (joined_columns.count(column.name))
            continue;
        joined_columns.insert(column.name);
        dedup_columns.push_back(column);
        auto & inserted = dedup_columns.back();
        
        if (left_table_columns.count(column.name) || !isValidIdentifierBegin(column.name.at(0)))
            inserted.name = right_table_prefix + column.name;
        original_names[inserted.name] = column.name;
        if (inserted.name != column.name)
            renames[column.name] = inserted.name;
    }
    columns_from_joined_table.swap(dedup_columns);
}
NamesWithAliases TableJoin::getNamesWithAliases(const NameSet & required_columns) const