Function getArrayJoinDataType

src/Interpreters/ArrayJoinAction.cpp:26–39

ArrayJoin support Array, Nullable(Array) and Map type

//ArrayJoin support Array, Nullable(Array) and Map type
std::shared_ptr<const DataTypeArray> getArrayJoinDataType(DataTypePtr type)
{
    using DataTypeArrayPtr = std::shared_ptr<const DataTypeArray>;
    // we don't assume what inside Nullable is always Array
    if (const auto * nullable_type = typeid_cast<const DataTypeNullable *>(type.get())) 
        type = nullable_type->getNestedType();

    if (auto array_type_ptr = typeid_cast<DataTypeArrayPtr>(type))
        return array_type_ptr;
    else if (const auto * map_type = typeid_cast<const DataTypeMap *>(type.get()))
        return typeid_cast<DataTypeArrayPtr>(map_type->getNestedType());

    return nullptr;
}

ColumnPtr getArrayJoinColumn(ColumnPtr column)
{