Evolve Iceberg table schema - Amazon Athena
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Evolve Iceberg table schema

Iceberg schema updates are metadata-only changes. No data files are changed when you perform a schema update.

The Iceberg format supports the following schema evolution changes:

  • Add – Adds a new column to a table or to a nested struct.

  • Drop – Removes an existing column from a table or nested struct.

  • Rename – Renames an existing column or field in a nested struct.

  • Reorder – Changes the order of columns.

  • Type promotion – Widens the type of a column, struct field, map key, map value, or list element. Currently, the following cases are supported for Iceberg tables:

    • integer to big integer

    • float to double

    • increasing the precision of a decimal type

You can use the DDL statements in this section to modify Iceberg table schema.