# Presto 316 Documentation

## 9.2. ALTER TABLE

## Synopsis

    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

## Description

Change the definition of an existing table.

## Examples

Rename table `users` to `people`:

    ALTER TABLE users RENAME TO people;

Add column `zip` to the `users` table:

    ALTER TABLE users ADD COLUMN zip varchar;

Drop column `zip` from the `users` table:

    ALTER TABLE users DROP COLUMN zip;

Rename column `id` to `user_id` in the `users` table:

    ALTER TABLE users RENAME COLUMN id TO user_id;

## See Also

CREATE TABLE