Function train_btree_index

pub async fn train_btree_index(
    data_source: Box<dyn TrainingSource + Send>,
    sub_index_trainer: &dyn BTreeSubIndex,
    index_store: &dyn IndexStore,
) -> Result<()>

Train a btree index from a stream of sorted page-size batches of values and row ids

Note: This is likely to change. It is unreasonable to expect the caller to do the sorting and re-chunking into page-size batches. This is left for simplicity as this feature is still a work in progress