mySQL - 将值插入单个列会导致多行？

Question

我在单列中插入多行。 这是表格：

CREATE TABLE Book (
   ID INT PRIMARY KEY AUTO_INCREMENT, 
   Title VARCHAR(100), 
   Author VARCHAR(40), 
   Pages INT, 
   Price FLOAT, 
   GENRE VARCHAR(30)
);

+----+---------------------------+----------------+-------+--------+-----------+
| ID | Book_Title                | Author         | Pages | Price  | GENRE     |
+----+---------------------------+----------------+-------+--------+-----------+
|  1 | The Lost Symbol           | Dan Brown      |   500 | 524.75 | Fiction   |
|  2 | Flamingo                  | NCERT          |   235 | 345.55 | Text Book |
|  3 | The Great Zoo of China    | Mathew Reilly  |   312 | 401.75 | Fantasy   |
|  4 | Walking from east to west | Ravi Zacharias |   240 | 220.45 | Biography |
|  5 | The Time Machine          | H.G Wells      |   245 | 120.45 | Novel     |
|  6 | Flamingo                  | NCERT          |   235 | 345.55 | Text Book |
+----+---------------------------+----------------+-------+--------+-----------+

ALTER TABLE Book ADD COLUMN Year INT;
INSERT INTO Book(Year) 
VALUES (1987), (2001), (1997), (1983), (1974), (2001);`

但我得到了完全出乎意料的结果：

+----+---------------------------+-------+--------+-----------+------+
| ID | Book_Title                | Pages | Price  | GENRE     | Year |
+----+---------------------------+-------+--------+-----------+------+
|  1 | The Lost Symbol           |   500 | 524.75 | Fiction   | NULL |
|  2 | Flamingo                  |   235 | 345.55 | Text Book | NULL |
|  3 | The Great Zoo of China    |   312 | 401.75 | Fantasy   | NULL |
|  4 | Walking from east to west |   240 | 220.45 | Biography | NULL |
|  5 | The Time Machine          |   245 | 120.45 | Novel     | NULL |
|  6 | Flamingo                  |   235 | 345.55 | Text Book | NULL |
|  7 | NULL                      |  NULL |   NULL | NULL      | 1987 |
|  8 | NULL                      |  NULL |   NULL | NULL      | 2001 |
|  9 | NULL                      |  NULL |   NULL | NULL      | 1997 |
| 10 | NULL                      |  NULL |   NULL | NULL      | 1983 |
| 11 | NULL                      |  NULL |   NULL | NULL      | 1974 |
| 12 | NULL                      |  NULL |   NULL | NULL      | 2001 |
+----+---------------------------+-------+--------+-----------+------+

PS：我已经删除了Author列

预期结果：

+----+---------------------------+-------+--------+-----------+------+
| ID | Book_Title                | Pages | Price  | GENRE     | Year |
+----+---------------------------+-------+--------+-----------+------+
|  1 | The Lost Symbol           |   500 | 524.75 | Fiction   | 1987 |
|  2 | Flamingo                  |   235 | 345.55 | Text Book | 2001 |
|  3 | The Great Zoo of China    |   312 | 401.75 | Fantasy   | 1997 |
|  4 | Walking from east to west |   240 | 220.45 | Biography | 1983 |
|  5 | The Time Machine          |   245 | 120.45 | Novel     | 1974 |
|  6 | Flamingo                  |   235 | 345.55 | Text Book | 2001 |
+----+---------------------------+-------+--------+-----------+------+

我提到了这些但没有用：

• Insert multiple rows into single column

• Adding only one value to the table in sql

Server version: 5.7.27-0ubuntu0.18.04.1

感谢所有帮助。

Answer 1

使用UPDATE 语句代替INSERT。插入将创建新记录，而您想向现有记录添加更多信息。

UPDATE Book SET `Year` = 1987 WHERE ID = 1;
UPDATE Book SET `Year` = 2001 WHERE ID = 2;
UPDATE Book SET `Year` = 1997 WHERE ID = 3;
UPDATE Book SET `Year` = 1983 WHERE ID = 4;
UPDATE Book SET `Year` = 1974 WHERE ID = 5;
UPDATE Book SET `Year` = 2001 WHERE ID = 6;

OR

UPDATE Book
SET `Year` = CASE `ID`
                WHEN 1 THEN 1987
                WHEN 2 THEN 2001 
                WHEN 3 THEN 1997 
                WHEN 4 THEN 1983
                WHEN 5 THEN 1974 
                WHEN 6 THEN 2001 
           END
WHERE `ID` IN (1,2,3,4,5,6); 

如果您不使用 ID 过滤器，建议在 case when 子句中添加 else 部分。