Update config

docs/source/user-guide/configs.md

@@ -91,7 +91,7 @@ Environment variables are read during `SessionConfig` initialisation so they mus
 | datafusion.execution.keep_partition_by_columns                          | false                     | Should DataFusion keep the columns used for partition_by in the output RecordBatches                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
 | datafusion.execution.skip_partial_aggregation_probe_ratio_threshold     | 0.8                       | Aggregation ratio (number of distinct groups / number of input rows) threshold for skipping partial aggregation. If the value is greater then partial aggregation will skip aggregation for further input                                                                                                                                                                                                                                                                                                                                                                                               |
 | datafusion.execution.skip_partial_aggregation_probe_rows_threshold      | 100000                    | Number of input rows partial aggregation partition should process, before aggregation ratio check and trying to switch to skipping aggregation mode                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
-| datafusion.execution.use_row_number_estimates_to_optimize_partitioning  | false                     | Should DataFusion use row number estimates at the input to decide whether increasing parallelism is beneficial or not. By default, only exact row numbers (not estimates) are used for decision. Setting this flag to `true` will likely produce better plans. We plan to make this the default in the future.                                                                                                                                                                                                                                                                                          |
+| datafusion.execution.use_row_number_estimates_to_optimize_partitioning  | false                     | Should DataFusion use row number estimates at the input to decide whether increasing parallelism is beneficial or not. By default, only exact row numbers (not estimates) are used for this decision. Setting this flag to `true` will likely produce better plans. if the source of statistics is accurate. We plan to make this the default in the future.                                                                                                                                                                                                                                            |
 | datafusion.optimizer.enable_distinct_aggregation_soft_limit             | true                      | When set to true, the optimizer will push a limit operation into grouped aggregations which have no aggregate expressions, as a soft limit, emitting groups once the limit is reached, before all rows in the group are read.                                                                                                                                                                                                                                                                                                                                                                           |
 | datafusion.optimizer.enable_round_robin_repartition                     | true                      | When set to true, the physical plan optimizer will try to add round robin repartitioning to increase parallelism to leverage more CPU cores                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
 | datafusion.optimizer.enable_topk_aggregation                            | true                      | When set to true, the optimizer will attempt to perform limit operations during aggregations, if possible                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |