# ALTER TABLE CHANGE COLUMN
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Changes the name, type, order or comment of a column in an Iceberg table.

**Note**  
`ALTER TABLE REPLACE COLUMNS` is not supported. Because `REPLACE COLUMNS` removes all columns and then adds new ones, it is not supported for Iceberg. `CHANGE COLUMN` is the preferred syntax for schema evolution. 

## Synopsis
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```
ALTER TABLE [{{db_name}}.]{{table_name}}
  CHANGE [COLUMN] {{col_old_name}} {{col_new_name}} {{column_type}} 
  [COMMENT {{col_comment}}] [FIRST|AFTER {{column_name}}]
```

## Example
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```
ALTER TABLE iceberg_table CHANGE comment blog_comment string AFTER id
```