Merge pull request ClickHouse#91688 from ClickHouse/backport/25.8/91040

Backport ClickHouse#91040 to 25.8: Fix reading dynamic subcolumns from materialized columns in mutations

Author: Avogar

src/Interpreters/TreeRewriter.cpp

@@ -1225,7 +1225,7 @@ bool TreeRewriterResult::collectUsedColumns(const ASTPtr & query, bool is_select
     /// Check for subcolumns in unknown required columns.
     if (!unknown_required_source_columns.empty() && (!storage || storage->supportsSubcolumns()))
     {
-        for (const NameAndTypePair & pair : source_columns_ordinary)
+        for (const NameAndTypePair & pair : required_source_columns)
         {
             for (auto it = unknown_required_source_columns.begin(); it != unknown_required_source_columns.end();)
             {

tests/queries/0_stateless/03741_subcolumns_of_materialized_columns_in_mutation.reference

@@ -0,0 +1 @@
+{}

tests/queries/0_stateless/03741_subcolumns_of_materialized_columns_in_mutation.sql

@@ -0,0 +1,7 @@
+drop table if exists test;
+create table test (s String, json JSON materialized s) engine=MergeTree order by tuple();
+insert into test select '{"a" : 42}';
+alter table test update s = '{}' where json.a = 42 settings mutations_sync=1;
+select * from test;
+drop table test;
+