我有一张这样的table
+----------------+----------------+----------+
| city | city2 | state |
+----------------+----------------+----------+
| abc | ghe | NY |
+----------------+----------------+----------+
| def | jkl | NY |
+----------------+----------------+----------+
而想要这样的结果在哪一个价值 city
以及 city2
在一列中合并 combined
```
+---------------------+
| combined |
+---------------------+
| abc |
+---------------------+
| def |
+---------------------+
| ghe |
+---------------------+
| jkl |
+---------------------+
2条答案
按热度按时间djp7away1#
yrwegjxp2#
一种方法使用
union all
;如果需要唯一值,请使用
union
而不是union all
.