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create table TableA(date datetime, abc int);
insert into TableA values
('2025-10-17 14:11:14', 0)
,('2025-10-17 14:12:11', 0)
,('2025-10-17 14:13:18', 0)
,('2025-10-17 14:14:15', 0)
,('2025-10-17 14:15:10', 0)
;
create table TableB(date datetime, xyz int);
insert into TableB values
('2025-10-17 14:12:26', 11)
,('2025-10-17 14:14:20', 22)
;
-- select * from TableA;
-- select * from TableB;
Records: 5 Duplicates: 0 Warnings: 0
Records: 2 Duplicates: 0 Warnings: 0
select *
from TableA a
left join TableB b
on b.date between (a.date- interval 30 second) and (a.date+ interval 30 second)
| date | abc | date | xyz |
|---|---|---|---|
| 2025-10-17 14:11:14 | 0 | null | null |
| 2025-10-17 14:12:11 | 0 | 2025-10-17 14:12:26 | 11 |
| 2025-10-17 14:13:18 | 0 | null | null |
| 2025-10-17 14:14:15 | 0 | 2025-10-17 14:14:20 | 22 |
| 2025-10-17 14:15:10 | 0 | null | null |
Update TableA a,TableB b
set a.abc=b.xyz
where b.date between (a.date- interval 30 second) and (a.date+ interval 30 second)
Rows matched: 2 Changed: 2 Warnings: 0
select * from TableA;
| date | abc |
|---|---|
| 2025-10-17 14:11:14 | 0 |
| 2025-10-17 14:12:11 | 11 |
| 2025-10-17 14:13:18 | 0 |
| 2025-10-17 14:14:15 | 22 |
| 2025-10-17 14:15:10 | 0 |