fix doc

Author: xiedeyantu

datafusion/sqllogictest/test_files/information_schema.slt

@@ -305,6 +305,7 @@ datafusion.optimizer.enable_sort_pushdown true
 datafusion.optimizer.enable_topk_aggregation true
 datafusion.optimizer.enable_topk_dynamic_filter_pushdown true
 datafusion.optimizer.enable_topk_repartition true
+datafusion.optimizer.enable_unions_to_filter false
 datafusion.optimizer.enable_window_limits true
 datafusion.optimizer.expand_views_at_output false
 datafusion.optimizer.filter_null_join_keys false

docs/source/user-guide/configs.md

@@ -168,6 +168,7 @@ The following configuration settings are available:
 | datafusion.optimizer.expand_views_at_output                             | false                     | When set to true, if the returned type is a view type then the output will be coerced to a non-view. Coerces `Utf8View` to `LargeUtf8`, and `BinaryView` to `LargeBinary`.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
 | datafusion.optimizer.enable_sort_pushdown                               | true                      | Enable sort pushdown optimization. When enabled, attempts to push sort requirements down to data sources that can natively handle them (e.g., by reversing file/row group read order). Returns **inexact ordering**: Sort operator is kept for correctness, but optimized input enables early termination for TopK queries (ORDER BY ... LIMIT N), providing significant speedup. Memory: No additional overhead (only changes read order). Future: Will add option to detect perfectly sorted data and eliminate Sort completely. Default: true                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
 | datafusion.optimizer.enable_leaf_expression_pushdown                    | true                      | When set to true, the optimizer will extract leaf expressions (such as `get_field`) from filter/sort/join nodes into projections closer to the leaf table scans, and push those projections down towards the leaf nodes.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
+| datafusion.optimizer.enable_unions_to_filter                            | false                     | When set to true, the logical optimizer will rewrite `UNION DISTINCT` branches that read from the same source and differ only by filter predicates into a single branch with a combined filter. This optimization is conservative and only applies when the branches share the same source and compatible wrapper nodes such as identical projections or aliases. See `datafusion/sqllogictest/test_files/union.slt` for examples.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
 | datafusion.explain.logical_plan_only                                    | false                     | When set to true, the explain statement will only print logical plans                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
 | datafusion.explain.physical_plan_only                                   | false                     | When set to true, the explain statement will only print physical plans                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
 | datafusion.explain.show_statistics                                      | false                     | When set to true, the explain statement will print operator statistics for physical plans                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |