MySQL选择一栏

Question

我们有下表:

+-------+----------+----------+
| id    | time1    | time2    |
+-------+----------+----------+
| 18413 | 00:00:00 | 00:00:24 |
| 18415 | 00:00:01 | 00:00:25 |
| 18557 | 00:00:02 | 00:01:31 |
| 18432 | 00:00:03 | 00:00:30 |
| 18428 | 00:00:04 | 00:00:28 |
+-------+----------+----------+

我们如何使用 mysql 选择来制作这个:

+-------+----------+
| time    | result |
+-------+----------+
| 00:00:00 | time1 |
| 00:00:01 | time1 |
| 00:00:02 | time1 |
| 00:00:03 | time1 |
| 00:00:04 | time1 |
| 00:00:24 | time2 |
+-------+----------+

我们将 time1 和 time2 混合在一列中，并按类型对它们进行分组，并在结果列中标记它们是 time1 还是 time2。

Answer 1

使用UNION:

SELECT  time1 as time,'time 1' as result
FROM TableName
UNION ALL
SELECT time2,'time 2' as result
FROM TableName

请参阅 Fiddle 中的示例.

编辑:

如果你想按照 time 列对它们进行排序，只需添加一个 ORDER BY 子句:

SELECT  time1 as time,'time 1' as result
FROM TableName
UNION ALL
SELECT time2,'time 2' as result
FROM TableName
ORDER BY T.time