Altering Apache Iceberg Tables

The ALTER command updates an Iceberg table’s schema in a new snapshot.

Syntax

ALTER TABLE [<table_path>.]<table_name> 
[ { ALTER | MODIFY | CHANGE } COLUMN ( <source_col_name> <new_col_name>{ data_type } ) ]
| [ ADD COLUMNS ( <column_name> data_type [, <column_name> data_type ... ] ) 
| [ DROP COLUMN <column_name> ]
| [ [ ADD | DROP ] PARTITION FIELD [ <column_name> | <partition_transform> ] ]
| [ RENAME [ COLUMN ] <old_column_name> [ TO ] <new_column_name> ]
| [ REFRESH METADATA ]

Parameters

{{< sql-section file="data/sql/apache-iceberg-tables.json" data="everythingAlter" >}}

Examples

Add a column

ALTER TABLE myTable ADD COLUMNS (address VARCHAR)

Change the data type of a column to BIGINT

ALTER TABLE myTable ALTER COLUMN id id BIGINT