删除mysql中包含空格的列

Question

我想知道如何在mysql中删除包含空格的列。 试过以下内容，并得到以下例外情况：

alter table test17 drop column [added column2];
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '[added column2]' at line 1

alter table test17 drop column 'added column2';
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ''added column2'' at line 1

alter table test17 drop column (added column2);
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '(added column2)' at line 1

感谢：）

Answer 1

首先，带空格的列名是BAD PRACTICE。然后，如果您确实要删除列，请改为使用反引号：

ALTER TABLE test17 DROP COLUMN `added_column2`;

Answer 2

尝试：

alter table test17 drop column `added column2`;

请注意，引号字符向左倾斜。

顺便说一下，如果你将空格作为标识符名称的一部分（例如函数，过程，表格，列等），那就是非常非常不良做法。

Answer 3

您应该尝试使用后退标记（“”“）来引用您的列名称。

ALTER TABLE test17 DROP COLUMN `added column2`;

OR

没有COLUMN字

ALTER TABLE test17 DROP `added column2`;