Aggregation Push-Down Optimization for Non-Aligned Series in Table Model

[ja...@gmail.com]

Hi all,

I'd like to share a new update we are bringing to the query engine. Wei-hao-Li has recently put together a great optimization that supports aggregation push-down for the table view of non-aligned series in Table Model. 

Why we need this:
Previously, running aggregations on non-aligned series could be resource-intensive and slow. By pushing the aggregation logic down closer to the data source during the table scan phase, we can significantly reduce the amount of raw data transferred and processed in memory. This leads to much faster query execution and lower overhead. **Es**

What changed:
The core of this update involves adding and refining several scan operators and planner nodes to handle these push-downs efficiently. Specifically, the changes introduce new implementations like `TreeNonAlignedDeviceViewAggregationScanOperator` and `NonAlignedAggregationTreeDeviceViewScanNode`, alongside updates to the `PushAggregationIntoTableScan` optimization rules. These ensure that Table Mode handles non-aligned series aggregations natively and optimally.

You can review the changes here: https://github.com/apache/iotdb/pull/17294

Best regards,
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Yuan Tian