Logic bug: Numeric TIME(6) cast rejects 0.999999

DROP DATABASE IF EXISTS db;

CREATE DATABASE db;

USE db;

CREATE TABLE t (

  id INT PRIMARY KEY,

  p INT NOT NULL,

  o INT NOT NULL,

  v INT NOT NULL,

  od DECIMAL(20,10) NOT NULL

);

INSERT INTO t VALUES

  (1, 1, 1, 10, 0.999999),

  (2, 1, 2, 20, 0.999998);

SELECT 'scalar_compare' AS phase;

SELECT id,

       CAST(od AS TIME(6)) AS num_cast,

       CAST(CAST(od AS CHAR) AS TIME(6)) AS char_cast

FROM t

ORDER BY id;

SHOW WARNINGS;

SELECT 'numeric_cast_query' AS phase;

SELECT id,

       ROW_NUMBER() OVER (PARTITION BY p ORDER BY o) AS rn,

       CAST(od AS TIME(6)) AS tm

FROM t

ORDER BY id;

SHOW WARNINGS;

SELECT 'string_cast_query' AS phase;

SELECT t1.id,

       (SELECT COUNT(*) FROM t AS t2 WHERE t2.p = t1.p AND t2.o <= t1.o) AS rn,

       CAST(CAST(t1.od AS CHAR) AS TIME(6)) AS tm

FROM t AS t1

ORDER BY t1.id;

SHOW WARNINGS;

DROP DATABASE db;