access-policy-restrictions.md

The following limitations apply to access policies:

  • A column can have only one access policy.

  • Column access policies cannot be set on columns of complex types other than native arrays.

  • Column access policies cannot be set for materialized columns on flex tables. While it is possible to set an access policy for the __raw__ column, doing so restricts access to the whole table.

  • Row access policies are invalid on temporary tables and tables with aggregate projections.

  • Access policy expressions cannot contain:

    • Subqueries

    • Aggregate functions

    • Analytic functions

    • User-defined transform functions (UDTF)

  • If the query optimizer cannot replace a deterministic expression that involves only constants with their computed values, it blocks all DML operations such as INSERT.