**Describe the bug**
Under certain conditions the equals comparison between String and Date yields the wrong result. Range Comparisons with greather-than-equals returns the correct result set.

**How to reproduce**
* Which ClickHouse server version to use: 21.2.5.5 (latest at the time of this issue)
* Which interface to use, if matters: HTTP (but should not matter)

```sql
CREATE TABLE default.myTable (
	myDay Date,
	myOrder Int32,
	someData String
) 
ENGINE = ReplacingMergeTree
PARTITION BY floor(toYYYYMMDD(myDay), -1)
ORDER BY (myOrder)
;

INSERT INTO default.myTable (myDay, myOrder) VALUES ('2021-01-01', 1);
INSERT INTO default.myTable (myDay, myOrder) VALUES ('2021-01-02', 2); // This row should be returned
INSERT INTO default.myTable (myDay, myOrder) VALUES ('2021-01-03', 3);

SELECT * FROM default.myTable mt
WHERE myDay = '2021-01-02';
```

**Expected behavior**
The last query in the example should yield the marked row. Instead it returns a empty result set.

There must be a connection to the used `PARTITION KEY`. The issue fails to reproduce as soon as I do any changes to the `PARTITION KEY` setting.

}
            else if (getConstant(args[0], block_with_constants, const_value, const_type))
            {
                if (isKeyPossiblyWrappedByMonotonicFunctions(args[1], context, key_column_num, key_expr_type, chain))
                {
                    key_arg_pos = 1;
                }
                else if (canConstantBeWrappedByMonotonicFunctions(args[1], key_column_num, key_expr_type, const_value, const_type))
                {
                    key_arg_pos = 1;
                    is_constant_transformed = true;
                }
                else if (
                    single_point && func_name == "equals"
                    && canConstantBeWrappedByFunctions(args[1], key_column_num, key_expr_type, const_value, const_type))
                {
                    key_arg_pos = 0;
                    is_constant_transformed = true;
                }
                else
                    return false;
            }
            else
                return false;
            if (key_column_num == static_cast<size_t>(-1))
                throw Exception("`key_column_num` wasn't initialized. It is a bug.", ErrorCodes::LOGICAL_ERROR);
            
            if (key_arg_pos == 1)
            {
                if (func_name == "less")