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}
```
, const DataTypes & argument_types_, const DataTypePtr & return_type_
        , std::optional<Diagnostic> diagnostic_, CastType cast_type_)
        : name(name_), monotonicity_for_range(std::move(monotonicity_for_range_))
        , argument_types(argument_types_), return_type(return_type_), diagnostic(std::move(diagnostic_))
        , cast_type(cast_type_)
    {
    }
    const DataTypes & getArgumentTypes() const override { return argument_types; }
    const DataTypePtr & getResultType() const override { return return_type; }
    ExecutableFunctionImplPtr prepare(const ColumnsWithTypeAndName & ) const override
    {
        try
        {
            return std::make_unique<ExecutableFunctionCast>(
                    prepareUnpackDictionaries(getArgumentTypes()[0], getResultType()), name, diagnostic);
        }
        catch (Exception & e)
        {
            if (diagnostic)
                e.addMessage("while converting source column " + backQuoteIfNeed(diagnostic->column_from) +
                             " to destination column " + backQuoteIfNeed(diagnostic->column_to));
            throw;
        }
    }
    String getName() const override { return name; }