**Describe what's wrong**

Query with rollup using same selected field name as the name of underlying column reports structure mismatch

**Does it reproduce on recent release?**

yes

**How to reproduce**

`21.9.2.17`

```sql
CREATE TABLE test
(
    `d` DateTime,
    `a` LowCardinality(String),
    `b` UInt64
)
ENGINE = MergeTree
PARTITION BY toDate(d)
ORDER BY d;

SELECT *
FROM (
    SELECT
        a,
        max((d, b)).2 AS value
    FROM test
    GROUP BY rollup(a)
)
WHERE a <> '';
```

**Expected behavior**

This used to return an ok result on v21.8

**Error message and/or stacktrace**

> Code: 352. DB::Exception: Block structure mismatch in (columns with identical name must have identical structure) stream: different columns:
> notEquals(a, '') LowCardinality(UInt8) ColumnLowCardinality(size = 0, UInt8(size = 0), ColumnUnique(size = 1, UInt8(size = 1)))
> notEquals(a, '') LowCardinality(UInt8) Const(size = 0, ColumnLowCardinality(size = 1, UInt8(size = 1), ColumnUnique(size = 2, UInt8(size = 2)))). (AMBIGUOUS_COLUMN_NAME) (version 21.9.2.17 (official build))



{
    String prefix(settings.offset, ' ');
    settings.out << prefix << "Filter column: " << filter_column_name << '\n';
    settings.out << prefix << "Mode: " << totalsModeToString(totals_mode, auto_include_threshold) << '\n';
    if (actions_dag)
    {
        bool first = true;
        auto expression = std::make_shared<ExpressionActions>(actions_dag);
        for (const auto & action : expression->getActions())
        {
            settings.out << prefix << (first ? "Actions: "
                                             : "         ");
            first = false;
            settings.out << action.toString() << '\n';
        }
    }
}
void TotalsHavingStep::describeActions(JSONBuilder::JSONMap & map) const
{
    map.add("Mode", totalsModeToString(totals_mode, auto_include_threshold));
    if (actions_dag)
    {
        map.add("Filter column", filter_column_name);
        auto expression = std::make_shared<ExpressionActions>(actions_dag);
        map.add("Expression", expression->toTree());
    }
}
}