public final Enum BatchFetchStyle

Dynamically builds its SQL based on the actual number of available ids. Does still limit to the batch-size defined on the entity/collection

The legacy algorithm where we keep a set of pre-built batch sizes based on org.hibernate.internal.util.collections.ArrayHelper#getBatchSizes. Batches are performed using the next-smaller pre-built batch size from the number of existing batchable identifiers.

For example, with a batch-size setting of 32 the pre-built batch sizes would be [32, 16, 10, 9, 8, 7, .., 1]. An attempt to batch load 31 identifiers would result in batches of 16, 10, and 5.

Still keeps the concept of pre-built batch sizes, but uses the next-bigger batch size and pads the extra identifier placeholders.

Using the same example of a batch-size setting of 32 the pre-built batch sizes would be the same. However, the attempt to batch load 31 identifiers would result just a single batch of size 32. The identifiers to load would be "padded" (aka, repeated) to make up the difference.