**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.
```

{
    bool nullable_src = src_column->isNullable();
    bool nullable_dst = dst_column->isNullable();
    ColumnPtr dst_not_null = JoinCommon::emptyNotNullableClone(dst_column);
    bool lowcard_src = JoinCommon::emptyNotNullableClone(src_column)->lowCardinality();
    bool lowcard_dst = dst_not_null->lowCardinality();
    bool change_lowcard = lowcard_src != lowcard_dst;
    if (nullable_src && !nullable_dst)
    {
        const auto * nullable = checkAndGetColumn<ColumnNullable>(*src_column);
        if (change_lowcard)
            dst_column = changeLowCardinality(nullable->getNestedColumnPtr(), dst_column);
        else
            dst_column = nullable->getNestedColumnPtr();
    }