```
CREATE TABLE a
(
    `number` UInt64,
    `x` MATERIALIZED x
)
ENGINE = MergeTree
ORDER BY number;
-- that should fail!

insert into a values (1);
Received exception from server (version 21.7.1):
Code: 47. DB::Exception: Received from localhost:9000. DB::Exception: Missing columns: 'x' while processing query: 'CAST(x, 'UInt8') AS x', required columns: 'x' 'x'. 
```
{
    auto range = getNameRange(columns, column_name);
    return range.first != range.second && range.first->name.length() > column_name.length();
}
bool ColumnsDescription::hasSubcolumn(const String & column_name) const
{
    return subcolumns.find(column_name) != subcolumns.end();
}
bool ColumnsDescription::hasInStorageOrSubcolumn(const String & column_name) const
{
    return has(column_name) || hasSubcolumn(column_name);
}
const ColumnDescription & ColumnsDescription::get(const String & column_name) const
{
    auto it = columns.get<1>().find(column_name);
    if (it == columns.get<1>().end())
        throw Exception("There is no column " + column_name + " in table.",
            ErrorCodes::NO_SUCH_COLUMN_IN_TABLE);
    return *it;
}
NamesAndTypesList ColumnsDescription::getAllPhysical() const
{
    NamesAndTypesList ret;
    for (const auto & col : columns)
        if (col.default_desc.kind != ColumnDefaultKind::Alias)
            ret.emplace_back(col.name, col.type);
    return ret;
}
Names ColumnsDescription::getNamesOfPhysical() const