hetu-core/hetu-docs/zh/sql/alter-table.md

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# ALTER TABLE
## 摘要
``` sql
ALTER TABLE name RENAME TO new_name
ALTER TABLE name ADD COLUMN column_name data_type [ COMMENT comment ] [ WITH ( property_name = expression [, ...] ) ]
ALTER TABLE name DROP COLUMN column_name
ALTER TABLE name RENAME COLUMN column_name TO new_column_name
```
## 说明
更改现有表的定义。
## 示例
将表 `users` 重命名为 `people`
ALTER TABLE users RENAME TO people;
`users` 表中添加 `zip` 列:
ALTER TABLE users ADD COLUMN zip varchar;
`users` 表中删除 `zip` 列:
ALTER TABLE users DROP COLUMN zip;
`users` 表中的 `id` 列重命名为 `user_id`
ALTER TABLE users RENAME COLUMN id TO user_id;
## 另请参见
[CREATE TABLE](./create-table.md)