Adding multiple columns AFTER a specific column in MySQL

问题

I need to add multiple columns to a table but position the columns after a column called lastname.

I have tried this:

ALTER TABLE `users` ADD COLUMN
(
    `count` smallint(6) NOT NULL,
    `log` varchar(12) NOT NULL,
    `status` int(10) unsigned NOT NULL
) 
AFTER `lastname`;

I get this error:

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 \') AFTER lastname\' at line 7

How can I use AFTER in a query like this?

回答1:

Try this

ALTER TABLE users
ADD COLUMN `count` SMALLINT(6) NOT NULL AFTER `lastname`,
ADD COLUMN `log` VARCHAR(12) NOT NULL AFTER `count`,
ADD COLUMN `status` INT(10) UNSIGNED NOT NULL AFTER `log`;

check the syntax

回答2:

If you want to add a single column after a specific field, then the following MySQL query should work:

ALTER TABLE users
    ADD COLUMN count SMALLINT(6) NOT NULL
    AFTER lastname

If you want to add multiple columns, then you need to use 'ADD' command each time for a column. Here is the MySQL query for this:

ALTER TABLE users
    ADD COLUMN count SMALLINT(6) NOT NULL,
    ADD COLUMN log VARCHAR(12) NOT NULL,
    ADD COLUMN status INT(10) UNSIGNED NOT NULL
    AFTER lastname

Point to note

In the second method, the last ADD COLUMN column should actually be the first column you want to append to the table.

E.g: if you want to add count, log, status in the exact order after lastname, then the syntax would actually be:

ALTER TABLE users
    ADD COLUMN log VARCHAR(12) NOT NULL AFTER lastname,
    ADD COLUMN status INT(10) UNSIGNED NOT NULL AFTER lastname,
    ADD COLUMN count SMALLINT(6) NOT NULL AFTER lastname

回答3:

You cannot mention multiple column names with commas using ADD COLUMN. You need to mention ADD COLUMN every time you define a new column.

回答4:

This one is correct:

ALTER TABLE `users`
    ADD COLUMN `count` SMALLINT(6) NOT NULL AFTER `lastname`,
    ADD COLUMN `log` VARCHAR(12) NOT NULL AFTER `count`,
    ADD COLUMN `status` INT(10) UNSIGNED NOT NULL AFTER `log`;

回答5:

ALTER TABLE `users` ADD COLUMN
`COLUMN NAME` DATATYPE(SIZE) AFTER `EXISTING COLUMN NAME`;

You can do it with this, working fine for me.

回答6:

One possibility would be to not bother about reordering the columns in the table and simply modify it by add the columns. Then, create a view which has the columns in the order you want -- assuming that the order is truly important. The view can be easily changed to reflect any ordering that you want. Since I can't imagine that the order would be important for programmatic applications, the view should suffice for those manual queries where it might be important.

回答7:

This works fine for me:

ALTER TABLE 'users'
ADD COLUMN 'count' SMALLINT(6) NOT NULL AFTER 'lastname',
ADD COLUMN 'log' VARCHAR(12) NOT NULL AFTER 'count',
ADD COLUMN 'status' INT(10) UNSIGNED NOT NULL AFTER 'log';

回答8:

The solution that worked for me with default value 0 is the following

ALTER TABLE reservations ADD COLUMN isGuest BIT DEFAULT 0

回答9:

ALTER TABLE listing ADD count INT(5), ADD log VARCHAR(200), ADD status VARCHAR(20) AFTER stat

It will give good results.

来源：https://stackoverflow.com/questions/17541312/adding-multiple-columns-after-a-specific-column-in-mysql

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mysql

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