With DISTINCTROW, NULLIF((-TRUE), c0) returns inconsistent results (-1 vs 1) between direct query and CTE/derived table rewrite.

1. 1. 1. Problem Description

When `DISTINCTROW` is used, the expression `NULLIF((- TRUE), c0)` returns different results in a direct query versus a query rewritten with a CTE/derived table: the direct query returns `-1`, while the rewritten query returns `1`. Without `DISTINCTROW`, both return `-1`.

1. 1. 1. How to Reproduce
         Execute the following SQL:

```sql
DROP DATABASE IF EXISTS vp_nullif;
CREATE DATABASE vp_nullif;
USE vp_nullif;

CREATE TABLE source (
c0 DATETIME NOT NULL,
UNIQUE KEY(c0)
) ENGINE=InnoDB;

INSERT INTO source VALUES
('2000-01-01 00:00:01'),
('2000-01-01 00:00:02');

CREATE TABLE l (
vp_rowid BIGINT NOT NULL PRIMARY KEY,
c0 DATETIME NOT NULL
) ENGINE=MyISAM;

CREATE TABLE r (
vp_rowid BIGINT NOT NULL PRIMARY KEY
) ENGINE=MyISAM;

INSERT INTO l VALUES
(1,'2000-01-01 00:00:01'),
(2,'2000-01-01 00:00:02');

INSERT INTO r VALUES (1),(2);

– Direct query
SELECT DISTINCTROW c0, c0, NULLIF((- TRUE), c0)
FROM source;

– Rewritten query (using derived table)
SELECT DISTINCTROW c0, c0, NULLIF((- TRUE), c0)
FROM (SELECT c0 FROM source) AS derived;
```

1. 1. 1. Expected Behavior
         Whether `DISTINCTROW` is used or not, and whether the query is rewritten with a CTE/derived table or not, `NULLIF((- TRUE), c0)` should return `-1` (since `c0` is a `DATETIME` and can never equal `-1`).

1. 1. 1. Actual Behavior

• Direct query (with `DISTINCTROW`): third column returns `-1`
• Rewritten query (with `DISTINCTROW` and derived table): third column returns `1`
• Without `DISTINCTROW`, both the direct query and the rewritten query return `-1`