Function flattenTupleLeafNames

src/DataTypes/NestedUtils.cpp:364–379

}

void flattenTupleLeafNames(const String & name, const DataTypePtr & type, Names & out)
{
    /// Mirrors the name generation of `flattenTupleRecursiveImpl`: descend only into flattenable
    /// tuples, joining each element name onto the prefix, and emit non-tuple types as leaves.
    const auto * tuple_type = tryGetFlattenableTuple(type);
    if (!tuple_type)
    {
        out.push_back(name);
        return;
    }

    const DataTypes & element_types = tuple_type->getElements();
    const Strings & element_names = tuple_type->getElementNames();
    for (size_t i = 0; i < element_types.size(); ++i)
        flattenTupleLeafNames(concatenateName(name, element_names[i]), element_types[i], out);
}

/// Flatten tuple columns: input a vector of columns, return a new vector with all tuples expanded
/// All tuples are flattened recursively