`load data` in cluster mode may cause out-of-order insertion, leading poor performance for long window

**Bug Description**
if `spark` is configured with multiple threads, say `local[*]` or `local[32]`, data loading will run in parallel, causing out-of-order loading.

It is ok for normal data insertion. But `long window optimization` requires that data is loaded mostly in order.

**Potential solution**
- remove the `in order loading` requirement for `long window`, by deleting the old entry and inserting the new one in the pre-aggr table.

The issue relates to the 'load data' operation in cluster mode and its interaction with long window optimization. Investigate the data loading path in the codebase, particularly looking for parallel execution logic. Examine the long window optimization implementation to understand the in-order requirement. Check if there are existing tests for data loading or window performance to verify changes.

Written by the indexing model from the issue text.