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CREATE TABLE dt (
`ID` VARCHAR(7),
`GROUP` VARCHAR(2),
`TIMESTAMP1` VARCHAR(23),
`col_OTHER` VARCHAR(7),
`TIMESTAMP2` VARCHAR(23)
);
INSERT INTO dt
(`ID`, `GROUP`, `TIMESTAMP1`, `col_OTHER`, `TIMESTAMP2`)
VALUES
('001', 'AA', '2021-04-02 15:02:33.319', 'mangos', null),
('002', 'BB', null, 'kiwis', null),
('004', 'AA', '2021-04-02 03:51:35.279', 'oranges', null),
('003', 'DD', '2021-04-03 18:24:23.469', 'oranges', '2021-04-03 18:22:23.469'),
('003', 'DD', null, 'bananas', '2021-04-03 15:02:33.319'),
('002', 'CC', '2021-04-04 11:02:51.313', 'apples', '2021-04-04 11:03:51.313');
SELECT *
FROM dt
WHERE COALESCE(TIMESTAMP1, '1970-01-01') < '2021-04-03'
OR COALESCE(TIMESTAMP1, '1970-01-01') < TIMESTAMP2
| ID | GROUP | TIMESTAMP1 | col_OTHER | TIMESTAMP2 |
|---|---|---|---|---|
| 001 | AA | 2021-04-02 15:02:33.319 | mangos | null |
| 002 | BB | null | kiwis | null |
| 004 | AA | 2021-04-02 03:51:35.279 | oranges | null |
| 003 | DD | null | bananas | 2021-04-03 15:02:33.319 |
| 002 | CC | 2021-04-04 11:02:51.313 | apples | 2021-04-04 11:03:51.313 |
SELECT *
FROM dt
WHERE COALESCE(TIMESTAMP1, '1970-01-01') < COALESCE(TIMESTAMP2, '2021-04-03')
| ID | GROUP | TIMESTAMP1 | col_OTHER | TIMESTAMP2 |
|---|---|---|---|---|
| 001 | AA | 2021-04-02 15:02:33.319 | mangos | null |
| 002 | BB | null | kiwis | null |
| 004 | AA | 2021-04-02 03:51:35.279 | oranges | null |
| 003 | DD | null | bananas | 2021-04-03 15:02:33.319 |
| 002 | CC | 2021-04-04 11:02:51.313 | apples | 2021-04-04 11:03:51.313 |