revert

be/src/olap/rowset_builder.cpp

@@ -415,7 +415,19 @@ void BaseRowsetBuilder::_build_current_tablet_schema(int64_t index_id,
                                                     indexes[i], ori_tablet_schema);
     }
     if (_tablet_schema->schema_version() > ori_tablet_schema.schema_version()) {
-        _tablet->update_max_version_schema(_tablet_schema);
+        // After schema change, should include extracted column
+        // For example: a table has two columns, k and v
+        // After adding a column v2, the schema version increases, max_version_schema needs to be updated.
+        // _tablet_schema includes k, v, and v2
+        // if v is a variant, need to add the columns decomposed from the v to the _tablet_schema.
+        if (_tablet_schema->num_variant_columns() > 0) {
+            TabletSchemaSPtr max_version_schema = std::make_shared<TabletSchema>();
+            max_version_schema->copy_from(*_tablet_schema);
+            max_version_schema->copy_extracted_columns(ori_tablet_schema);
+            _tablet->update_max_version_schema(max_version_schema);
+        } else {
+            _tablet->update_max_version_schema(_tablet_schema);
+        }
     }
 
     _tablet_schema->set_table_id(table_schema_param->table_id());

be/src/olap/tablet_schema.cpp

@@ -1222,6 +1222,23 @@ bool TabletSchema::is_dropped_column(const TabletColumn& col) const {
     return it == _field_name_to_index.end() || _cols[it->second]->unique_id() != col.unique_id();
 }
 
+void TabletSchema::copy_extracted_columns(const TabletSchema& src_schema) {
+    std::unordered_set<int32_t> variant_columns;
+    for (const auto& col : columns()) {
+        if (col->is_variant_type()) {
+            variant_columns.insert(col->unique_id());
+        }
+    }
+    for (const TabletColumnPtr& col : src_schema.columns()) {
+        if (col->is_extracted_column() && variant_columns.contains(col->parent_unique_id())) {
+            ColumnPB col_pb;
+            col->to_schema_pb(&col_pb);
+            TabletColumn new_col(col_pb);
+            append_column(new_col, ColumnType::VARIANT);
+        }
+    }
+}
+
 void TabletSchema::reserve_extracted_columns() {
     for (auto it = _cols.begin(); it != _cols.end();) {
         if (!(*it)->is_extracted_column()) {

be/src/olap/tablet_schema.h

@@ -462,6 +462,9 @@ class TabletSchema : public MetadataAdder<TabletSchema> {
 
     bool is_dropped_column(const TabletColumn& col) const;
 
+    // copy extracted columns from src_schema
+    void copy_extracted_columns(const TabletSchema& src_schema);
+
     // only reserve extracted columns
     void reserve_extracted_columns();