Merge pull request ClickHouse#87072 from ClickHouse/backport/25.8/87040

antonio2368 · web-flow · commit 6008911bbacd · 2025-09-13T14:33:16.000+02:00
Backport ClickHouse#87040 to 25.8: Correctly cast output after splitting prewhere
diff --git a/src/Storages/MergeTree/MergeTreeSplitPrewhereIntoReadSteps.cpp b/src/Storages/MergeTree/MergeTreeSplitPrewhereIntoReadSteps.cpp
@@ -157,7 +157,7 @@ const ActionsDAG::Node & addCast(
         const ActionsDAG::Node & node_to_cast,
         const DataTypePtr & to_type)
 {
-    if (!node_to_cast.result_type->equals(*to_type))
+    if (node_to_cast.result_type->equals(*to_type))
         return node_to_cast;  /// NOLINT(bugprone-return-const-ref-from-parameter)
 
     const auto & new_node = dag->addCast(node_to_cast, to_type, {});

Original file line number	Diff line number	Diff line change
`@@ -157,7 +157,7 @@ const ActionsDAG::Node & addCast(`
`157`	`157`	`const ActionsDAG::Node & node_to_cast,`
`158`	`158`	`const DataTypePtr & to_type)`
`159`	`159`	`{`
`160`		`- if (!node_to_cast.result_type->equals(*to_type))`
	`160`	`+ if (node_to_cast.result_type->equals(*to_type))`
`161`	`161`	`return node_to_cast; /// NOLINT(bugprone-return-const-ref-from-parameter)`
`162`	`162`
`163`	`163`	`const auto & new_node = dag->addCast(node_to_cast, to_type, {});`