Question

我有一张包含很多行的表（大约1,500）。在city_name列中，某些单元格具有城市名称，以（CD）结尾。我希望在没有（CD）的情况下更新带有（CD）的单元格。这是我的表的预览：

+---------+-----------------------+---------+
| city_id | city_name             | id_dept |
+---------+-----------------------+---------+
|       1 | El Encanto (CD)       |       1 |
|       2 | La Chorrera (CD)      |       1 |
|       3 | La Pedrera (CD)       |       1 |
|       4 | La Victoria (CD)      |       1 |
|       5 | Leticia               |       1 |
|       6 | Miriti Parana (CD)    |       1 |
|       7 | Puerto Alegria (CD)   |       1 |
|       8 | Puerto Arica (CD)     |       1 |
|       9 | Puerto Nariño         |       1 |
|      10 | Puerto Santander (CD) |       1 |
+---------+-----------------------+---------+
10 rows in set (0.00 sec)

这就是我想要的：

+---------+-----------------------+---------+
| city_id | city_name             | id_dept |
+---------+-----------------------+---------+
|       1 | El Encanto            |       1 |
|       2 | La Chorrera           |       1 |
|       3 | La Pedrera            |       1 |
|       4 | La Victoria           |       1 |
|       5 | Leticia               |       1 |
|       6 | Miriti Parana         |       1 |
|       7 | Puerto Alegria        |       1 |
|       8 | Puerto Arica          |       1 |
|       9 | Puerto Nariño         |       1 |
|      10 | Puerto Santander      |       1 |
+---------+-----------------------+---------+
10 rows in set (0.00 sec)

我明白我可以用（CD）选择所有行：

SELECT * FROM city WHERE city_name LIKE ( "%(CD)%" )

但是如何删除（CD）：

UPDATE city SET city_name = "" WHERE city_name LIKE( "%(CD)%" )

Answer 1

您可以使用REPLACE()功能

UPDATE city SET city_name = REPLACE(city_name, '(CD)', '') 
WHERE city_name LIKE( "%(CD)%" )

Answer 2

如果它总是以“（CD）”结尾，你想要将它们砍掉，你可以这样做：

UPDATE city
SET city_name = LEFT(city_name, CHAR_LENGTH(city_name) - 5)
WHERE city_name LIKE '% (CD)';

如果MySQL上的字符串存在，则更新单元格内容

2 个答案: