假设有一个名为table_name
的表格,其中有以下数据:
year | week | data |
---|---|---|
2021 | 0 | abc |
2020 | 52 | def |
2020 | 1 | ghi |
可以使用UNION
和子查询来合并今年的0周和去年的52周:
SELECT *
FROM (
SELECT * FROM table_name WHERE year = 2021 AND week = 0
UNION ALL
SELECT * FROM table_name WHERE year = 2020 AND week = 52
) AS combined_data;
这将返回以下结果:
year | week | data |
---|---|---|
2021 | 0 | abc |
2020 | 52 | def |