--- tests for timezone ---
SHOW VARIABLES time_zone;

+-----------+
| TIME_ZONE |
+-----------+
| UTC       |
+-----------+

SHOW VARIABLES system_time_zone;

+------------------+
| SYSTEM_TIME_ZONE |
+------------------+
| UTC              |
+------------------+

select timezone();

+------------+
| timezone() |
+------------+
| UTC        |
+------------+

CREATE TABLE test(d double, ts timestamp_ms time index);

Affected Rows: 0

INSERT INTO test values
       (1, '2024-01-01 00:00:00'),
       (2, '2024-01-02 08:00:00'),
       (3, '2024-01-03 16:00:00'),
       (4, '2024-01-04 00:00:00'),
       (5, '2024-01-05 00:00:00+08:00');

Affected Rows: 5

SELECT * from test;

+-----+---------------------+
| d   | ts                  |
+-----+---------------------+
| 1.0 | 2024-01-01T00:00:00 |
| 2.0 | 2024-01-02T08:00:00 |
| 3.0 | 2024-01-03T16:00:00 |
| 4.0 | 2024-01-04T00:00:00 |
| 5.0 | 2024-01-04T16:00:00 |
+-----+---------------------+

SELECT * from test where ts >= '2024-01-02 08:00:00';

+-----+---------------------+
| d   | ts                  |
+-----+---------------------+
| 2.0 | 2024-01-02T08:00:00 |
| 3.0 | 2024-01-03T16:00:00 |
| 4.0 | 2024-01-04T00:00:00 |
| 5.0 | 2024-01-04T16:00:00 |
+-----+---------------------+

SELECT * from test where ts <= '2024-01-03 16:00:00';

+-----+---------------------+
| d   | ts                  |
+-----+---------------------+
| 1.0 | 2024-01-01T00:00:00 |
| 2.0 | 2024-01-02T08:00:00 |
| 3.0 | 2024-01-03T16:00:00 |
+-----+---------------------+

select date_format(ts, '%Y-%m-%d %H:%M:%S:%3f') from test;

+----------------------------------------------------+
| date_format(test.ts,Utf8("%Y-%m-%d %H:%M:%S:%3f")) |
+----------------------------------------------------+
| 2024-01-01 00:00:00:000                            |
| 2024-01-02 08:00:00:000                            |
| 2024-01-03 16:00:00:000                            |
| 2024-01-04 00:00:00:000                            |
| 2024-01-04 16:00:00:000                            |
+----------------------------------------------------+

select to_unixtime('2024-01-02 00:00:00');

+------------------------------------------+
| to_unixtime(Utf8("2024-01-02 00:00:00")) |
+------------------------------------------+
| 1704153600                               |
+------------------------------------------+

select to_unixtime('2024-01-02T00:00:00+08:00');

+------------------------------------------------+
| to_unixtime(Utf8("2024-01-02T00:00:00+08:00")) |
+------------------------------------------------+
| 1704124800                                     |
+------------------------------------------------+

--- UTC+8 ---
SET TIME_ZONE = '+8:00';

Affected Rows: 0

SHOW VARIABLES time_zone;

+-----------+
| TIME_ZONE |
+-----------+
| +08:00    |
+-----------+

SHOW VARIABLES system_time_zone;

+------------------+
| SYSTEM_TIME_ZONE |
+------------------+
| UTC              |
+------------------+

select timezone();

+------------+
| timezone() |
+------------+
| +08:00     |
+------------+

SELECT * from test;

+-----+---------------------+
| d   | ts                  |
+-----+---------------------+
| 1.0 | 2024-01-01T00:00:00 |
| 2.0 | 2024-01-02T08:00:00 |
| 3.0 | 2024-01-03T16:00:00 |
| 4.0 | 2024-01-04T00:00:00 |
| 5.0 | 2024-01-04T16:00:00 |
+-----+---------------------+

SELECT * from test where ts >= '2024-01-02 08:00:00';

+-----+---------------------+
| d   | ts                  |
+-----+---------------------+
| 2.0 | 2024-01-02T08:00:00 |
| 3.0 | 2024-01-03T16:00:00 |
| 4.0 | 2024-01-04T00:00:00 |
| 5.0 | 2024-01-04T16:00:00 |
+-----+---------------------+

SELECT * from test where ts <= '2024-01-03 16:00:00';

+-----+---------------------+
| d   | ts                  |
+-----+---------------------+
| 1.0 | 2024-01-01T00:00:00 |
| 2.0 | 2024-01-02T08:00:00 |
+-----+---------------------+

select date_format(ts, '%Y-%m-%d %H:%M:%S:%3f') from test;

+----------------------------------------------------+
| date_format(test.ts,Utf8("%Y-%m-%d %H:%M:%S:%3f")) |
+----------------------------------------------------+
| 2024-01-01 08:00:00:000                            |
| 2024-01-02 16:00:00:000                            |
| 2024-01-04 00:00:00:000                            |
| 2024-01-04 08:00:00:000                            |
| 2024-01-05 00:00:00:000                            |
+----------------------------------------------------+

select to_unixtime('2024-01-02 00:00:00');

+------------------------------------------+
| to_unixtime(Utf8("2024-01-02 00:00:00")) |
+------------------------------------------+
| 1704124800                               |
+------------------------------------------+

select to_unixtime('2024-01-02 00:00:00+08:00');

+------------------------------------------------+
| to_unixtime(Utf8("2024-01-02 00:00:00+08:00")) |
+------------------------------------------------+
| 1704124800                                     |
+------------------------------------------------+

--- UTC-8 ---
SET SESSION TIME_ZONE = '-8:00';

Affected Rows: 0

SHOW VARIABLES time_zone;

+-----------+
| TIME_ZONE |
+-----------+
| -08:00    |
+-----------+

SHOW VARIABLES system_time_zone;

+------------------+
| SYSTEM_TIME_ZONE |
+------------------+
| UTC              |
+------------------+

select timezone();

+------------+
| timezone() |
+------------+
| -08:00     |
+------------+

SELECT * from test;

+-----+---------------------+
| d   | ts                  |
+-----+---------------------+
| 1.0 | 2024-01-01T00:00:00 |
| 2.0 | 2024-01-02T08:00:00 |
| 3.0 | 2024-01-03T16:00:00 |
| 4.0 | 2024-01-04T00:00:00 |
| 5.0 | 2024-01-04T16:00:00 |
+-----+---------------------+

SELECT * from test where ts >= '2024-01-02 08:00:00';

+-----+---------------------+
| d   | ts                  |
+-----+---------------------+
| 3.0 | 2024-01-03T16:00:00 |
| 4.0 | 2024-01-04T00:00:00 |
| 5.0 | 2024-01-04T16:00:00 |
+-----+---------------------+

SELECT * from test where ts <= '2024-01-03 16:00:00';

+-----+---------------------+
| d   | ts                  |
+-----+---------------------+
| 1.0 | 2024-01-01T00:00:00 |
| 2.0 | 2024-01-02T08:00:00 |
| 3.0 | 2024-01-03T16:00:00 |
| 4.0 | 2024-01-04T00:00:00 |
+-----+---------------------+

select date_format(ts, '%Y-%m-%d %H:%M:%S:%3f') from test;

+----------------------------------------------------+
| date_format(test.ts,Utf8("%Y-%m-%d %H:%M:%S:%3f")) |
+----------------------------------------------------+
| 2023-12-31 16:00:00:000                            |
| 2024-01-02 00:00:00:000                            |
| 2024-01-03 08:00:00:000                            |
| 2024-01-03 16:00:00:000                            |
| 2024-01-04 08:00:00:000                            |
+----------------------------------------------------+

select to_unixtime('2024-01-02 00:00:00');

+------------------------------------------+
| to_unixtime(Utf8("2024-01-02 00:00:00")) |
+------------------------------------------+
| 1704182400                               |
+------------------------------------------+

select to_unixtime('2024-01-02 00:00:00+08:00');

+------------------------------------------------+
| to_unixtime(Utf8("2024-01-02 00:00:00+08:00")) |
+------------------------------------------------+
| 1704124800                                     |
+------------------------------------------------+

drop table test;

Affected Rows: 0

-- revert timezone to UTC
SET LOCAL TIME_ZONE = 'UTC';

Affected Rows: 0

SHOW VARIABLES time_zone;

+-----------+
| TIME_ZONE |
+-----------+
| UTC       |
+-----------+

select timezone();

+------------+
| timezone() |
+------------+
| UTC        |
+------------+