You can define fallback for join indexes. The criteria for deciding whether to define a join index with fallback are similar to those used for deciding whether to define fallback on base tables.
If you do not define fallback for a join index and an AMP is down, then the following additional criteria become critical:
- The join index cannot be used by the Optimizer to solve its covered queries.
- The base tables on which the join index is defined cannot be updated.
You cannot use the NO FALLBACK option and the NO FALLBACK default on platforms optimized for fallback.