You can now use reusable column aliases in GoogleSQL.

You can now use reusable column aliases in GoogleSQL. This feature lets you define an alias for an expression in the SELECT clause of a SQL query and immediately reference that alias within the same SELECT list or in the WHERE clause of the same query block.

Reusable column aliases also streamline the migration of workloads from other data warehouses such as Snowflake and Teradata, by supporting their syntax.

This feature is generally available, and is opt-in only. To use reusable column aliases, you must first enable the feature.