如何從MySQL中的表中刪除列

本文翻譯自：How to delete a column from a table in MySQL

Given the table created using: 給定使用以下表創建的表：

CREATE TABLE tbl_Country
(
  CountryId INT NOT NULL AUTO_INCREMENT,
  IsDeleted bit,
  PRIMARY KEY (CountryId) 
)

How can I delete the column IsDeleted ? 如何刪除列IsDeleted ？

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#1樓

參考：https://stackoom.com/question/wbqI/如何從MySQL中的表中刪除列

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#2樓

ALTER TABLE tbl_Country DROP COLUMN IsDeleted;

Here's a working example. 這是一個有效的例子。

Note that the COLUMN keyword is optional, as MySQL will accept just DROP IsDeleted . 請注意， COLUMN關鍵字是可選的，因爲MySQL只接受DROP IsDeleted 。 Also, to drop multiple columns, you have to separate them by commas and include the DROP for each one. 另外，要刪除多個列，必須用逗號分隔它們，併爲每個列包含DROP 。

ALTER TABLE tbl_Country
  DROP COLUMN IsDeleted,
  DROP COLUMN CountryName;

This allows you to DROP , ADD and ALTER multiple columns on the same table in the one statement. 這允許您在一個語句中的同一個表上DROP ， ADD和ALTER多個列。 From the MySQL reference manual : 從MySQL參考手冊 ：

You can issue multiple ADD , ALTER , DROP , and CHANGE clauses in a single ALTER TABLE statement, separated by commas. 您可以在單個ALTER TABLE語句中發出多個ADD ， ALTER ， DROP和CHANGE子句，以逗號分隔。 This is a MySQL extension to standard SQL, which permits only one of each clause per ALTER TABLE statement. 這是標準SQL的MySQL擴展，它只允許每個ALTER TABLE語句中的一個子句。

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#3樓

要刪除列，請使用此項，

ALTER TABLE `tbl_Country` DROP `your_col`

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#4樓

ALTER TABLE tbl_Country DROP columnName;

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#5樓

使用ALTER ：

ALTER TABLE `tbl_Country` DROP COLUMN `column_name`;

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#6樓

ALTER TABLE `tablename` DROP `columnname`;

要麼，

ALTER TABLE `tablename` DROP COLUMN `columnname`;