Always reproduced:

```
milovidov-desktop :) create table table_map (a Map(String, String), b String) engine = MergeTree() order by a;

CREATE TABLE table_map
(
    `a` Map(String, String),
    `b` String
)
ENGINE = MergeTree
ORDER BY a

Query id: 8f8120c1-c165-452a-815f-2bcae3957e2a

Ok.

0 rows in set. Elapsed: 0.002 sec. 

milovidov-desktop :) SELECT b FROM table_map WHERE a = map('name', NULL, '', NULL)

SELECT b
FROM table_map
WHERE a = {'name', NULL, '', NULL}
```
if (result_is_nullable)
        {
            return [wrapper, source_is_nullable]
                (ColumnsWithTypeAndName & arguments, const DataTypePtr & result_type, const ColumnNullable *, size_t input_rows_count) -> ColumnPtr
            {
                
                const auto & nullable_type = static_cast<const DataTypeNullable &>(*result_type);
                const auto & nested_type = nullable_type.getNestedType();
                ColumnsWithTypeAndName tmp_args;
                if (source_is_nullable)
                    tmp_args = createBlockWithNestedColumns(arguments);
                else
                    tmp_args = arguments;
                const ColumnNullable * nullable_source = nullptr;
                
                if (source_is_nullable)
                {
                    if (arguments.size() != 1)
                        throw Exception("Invalid number of arguments", ErrorCodes::LOGICAL_ERROR);
                    nullable_source = typeid_cast<const ColumnNullable *>(arguments.front().column.get());
                }
                
                auto tmp_res = wrapper(tmp_args, nested_type, nullable_source, input_rows_count);
                
                if (!tmp_res)
                    throw Exception("Couldn't convert " + arguments[0].type->getName() + " to "
                                    + nested_type->getName() + " in " + " prepareRemoveNullable wrapper.", ErrorCodes::LOGICAL_ERROR);
                return wrapInNullable(tmp_res, arguments, nested_type, input_rows_count);
            };
        }