如何在现有表格的特定位置插入列? [英] How to insert columns at a specific position in existing table?

问题描述

我创建了一个有85列的表格，但是我错过了一列.错过的栏应该是第57栏.我不想删除该表并再次创建它.我希望编辑该表并在第57个索引中添加一列.

I created a table with 85 columns but I missed one column. The missed column should be the 57th one. I don't want to drop that table and create it again. I'm looking to edit that table and add a column in the 57th index.

我尝试了以下查询，但在表末尾添加了一列.

I tried the following query but it added a column at the end of the table.

ALTER table table_name
Add column column_name57 integer

如何将列插入特定位置?

How can I insert columns into a specific position?

推荐答案

ALTER TABLE默认情况下在表的末尾添加新列.使用AFTER指令将其放置在表格中的某个位置:

ALTER TABLE by default adds new columns at the end of the table. Use the AFTER directive to place it in a certain position within the table:

ALTER table table_name
    Add column column_name57 integer AFTER column_name56

来自mysql文档

要在表行中的特定位置添加一列，请使用FIRST或AFTER col_name .默认为最后添加该列.您还可以在CHANGE或MODIFY操作中使用FIRST和AFTER对表中的列进行重新排序.

To add a column at a specific position within a table row, use FIRST or AFTERcol_name. The default is to add the column last. You can also use FIRST and AFTER in CHANGE or MODIFY operations to reorder columns within a table.

http://dev.mysql.com/doc/refman/5.1/en/alter-table.html

我为PostgreSQL搜索了此文件，但

I googled for this for PostgreSQL but it seems to be impossible.

这篇关于如何在现有表格的特定位置插入列?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！