Question

好的，我有一个名为cities的表格，列id,city,state,county,zip_code,url

然后我有第二个名为us_url的表，其中包含列：id, url, city, state

cities表具有city和state的唯一键以防止重复（因此，如果我导入新记录，如果城市+州组合已经存在，请跳过它）。

目前，us_url只是暂时的。我想将该表中的数据复制到cities表。如果是city＆amp; state中不存在cities组合，插入us_url表中的新记录。如果确实存在，请使用cities.url值更新us_url.url列。

我试过这个：

INSERT INTO cities (id, city, state, county, zip_code, url) 
            VALUES(,us_url.city,us_url.state,,url) 
            ON DUPLICATE KEY UPDATE url=VALUES(url);

但这给了我一个语法错误，我甚至不确定这是否正确。

我希望这是有道理的。非常感谢任何帮助。

Answer 1

insert into cities (id,city, state,url) (select id,city,state,url from us_url) on duplicate key update url=VALUES(url);

应该做的诀窍：

mysql> select * from cities;
+------+------+-------+---------+----------+------+
| id   | city | state | country | zip_code | url  |
+------+------+-------+---------+----------+------+
| 1    | 2    | 3     | 4       | 5        | 6    |
+------+------+-------+---------+----------+------+
1 row in set (0.00 sec)

mysql> select * from us_url;
+------+------+------+-------+
| id   | url  | city | state |
+------+------+------+-------+
| 1    | 10   | 2    | 3     |
| 2    | 11   | 3    | 4     |
+------+------+------+-------+
2 rows in set (0.00 sec)

mysql> insert into cities (id,city, state,url) (select id,city,state,url from us_url) on duplicate key update url=VALUES(url);
Query OK, 1 row affected (0.01 sec)
Records: 2  Duplicates: 0  Warnings: 0

mysql> select * from cities;
+------+------+-------+---------+----------+------+
| id   | city | state | country | zip_code | url  |
+------+------+-------+---------+----------+------+
| 1    | 2    | 3     | 4       | 5        | 10   |
| 2    | 3    | 4     | NULL    | NULL     | 11   |
+------+------+-------+---------+----------+------+
2 rows in set (0.00 sec)

mysql>

记录存在时的MYSQL更新表

1 个答案: