yujun777 commented on code in PR #68646:
URL: https://github.com/apache/doris/pull/68646#discussion_r4143670230


##########
fe/fe-core/src/main/java/org/apache/doris/alter/Alter.java:
##########
@@ -373,8 +374,30 @@ private boolean 
processAlterOlapTableInternal(List<AlterOp> alterOps, OlapTable
             throw new DdlException("Invalid alter operations: " + 
currentAlterOps);
         }
         if (needChangeMTMVState(alterOps)) {
-            Env.getCurrentEnv().getMtmvService()
-                .alterTable(oldBaseTableInfo, newBaseTableInfo, 
currentAlterOps.hasReplaceTableOp());
+            // Which columns an operation's effect on a view turns on is the 
operation's to say, see
+            // AlterOp#queryJudgedColumnNames, and every clause of the alter 
has to name them: a batch that
+            // mixes a dropped column with a type change is decided by neither 
-- no query says anything
+            // about a type change -- and stays invalidated the way it was 
before the queries were asked at
+            // all. Each of them also has to have reached the table. A schema 
change that is not a light one
+            // is applied by a job, which may not have run where this hook 
runs: the table still holds the
+            // column the change is about, every query still analyses against 
it, and an invalidation
+            // decided on that answer would be about the table from before the 
change. What is asked is
+            // whether the change has reached the table, which is the same 
fact the re-analysis reads, so
+            // the two answers cannot disagree.
+            boolean judgedByQuery = alterOps.stream().allMatch(op -> 
!op.queryJudgedColumnNames().isEmpty()
+                    && op.hasReachedTheTable(olapTable));
+            // The names of those columns go to the hook rather than a 
verdict: what the judgement is about
+            // is the column, and the hook holds the query's answer against it 
-- both while asking, in case
+            // the query can reach the name some other way now, and once it 
has answered, in case the table
+            // is no longer the one that answered. See MTMVRelationManager.
+            MTMVHookService.QueryJudgedChange queryJudgedChange = judgedByQuery
+                    ? new MTMVHookService.QueryJudgedChange(
+                            
alterOps.stream().map(AlterOp::queryJudgedColumnNames).flatMap(Set::stream)
+                                    .collect(Collectors.toSet()),
+                            () -> alterOps.stream().allMatch(op -> 
op.hasReachedTheTable(olapTable)))
+                    : null;
+            Env.getCurrentEnv().getMtmvService().alterTable(oldBaseTableInfo, 
newBaseTableInfo,

Review Comment:
   Agreed, and this one is not fixed here: it is not a precision question like 
the others but the window between `SchemaChangeHandler.process` publishing the 
new column and this hook invalidating the views that read it, and closing it 
means the invalidation has to be established before the new schema is visible 
to a planner -- either by moving the whole-MV decision to where the write lock 
is still held, or by a barrier the rewrite's plan building respects. It needs a 
decision on which of the two, so I have not guessed at it in this commit.
   



##########
fe/fe-core/src/main/java/org/apache/doris/mtmv/MTMVRelationManager.java:
##########
@@ -349,34 +359,167 @@ public void dropTable(Table table) {
         // because a dropped table is the one change whose query is gone 
beyond doubt. What the two record
         // is the same state either way. Unlike a rename it stays an 
invalidation: the table is gone for
         // good, so the state is not something a later alter can make obsolete.
-        processBaseTableChange(new BaseTableInfo(table), "The base table has 
been deleted:", false);
+        processBaseTableChange(new BaseTableInfo(table), "The base table has 
been deleted:", null);
     }
 
     /**
      * update mtmv status to `SCHEMA_CHANGE`.
      *
      * @param isReplace
+     * @param queryJudgedColumns the names the alter gives the table or takes 
away from it, which leave the
+     *                           judgement about each MV's state to that MV's 
own query, or null when the
+     *                           alter is not one a query decides. The names 
are carried rather than judged
+     *                           before the call because the judgement is 
about them; see
+     *                           {@code AlterOp#queryJudgedColumnNames} for 
which operations name one, and
+     *                           {@link #invalidateMvUnlessQueryHolds} for 
what is asked about it. A rename
+     *                           of the base table names no column: it is left 
to the record below, which
+     *                           says what the MV that keeps spelling the old 
name needs to hear
      */
     @Override
-    public void alterTable(BaseTableInfo oldTableInfo, Optional<BaseTableInfo> 
newTableInfo, boolean isReplace) {
+    public void alterTable(BaseTableInfo oldTableInfo, Optional<BaseTableInfo> 
newTableInfo, boolean isReplace,
+            QueryJudgedChange queryJudgedChange) {
         // when replace, need deal two table
         if (isReplace) {
             // REPLACE TABLE already invalidates the IVM baseline explicitly, 
see Alter#processReplaceTable
-            processBaseTableChange(newTableInfo.get(), "The base table has 
been updated:", false);
+            processBaseTableChange(newTableInfo.get(), "The base table has 
been updated:", null);
         }
-        boolean renamed = !isReplace && newTableInfo.isPresent()
-                && !Objects.equals(oldTableInfo.getTableName(), 
newTableInfo.get().getTableName());
-        // A rename is the one change whose query check is skipped: the MV 
query keeps spelling the old
-        // name, so it is unanalyzable by construction, and the reason it 
would be invalidated with --
-        // "the query is no longer analyzable" -- says less than the message 
this call records anyway.
-        boolean checkQueryUsable = !renamed;
-        processBaseTableChange(oldTableInfo, "The base table has been 
updated:", checkQueryUsable);
+        processBaseTableChange(oldTableInfo, "The base table has been 
updated:", queryJudgedChange);
     }
 
 
     /**
-     * An MV's query is only as good as the base table schema it was analyzed 
against. Re-analyzing the
-     * MV query here (right after the alter was applied) is what detects a 
changed column identity:
+     * Whether the query, as it is analysed now, reads a column of any of 
these names, and reads it where
+     * the change can reach it.
+     *
+     * <p>There are two places a name is the change's to answer for. One is a 
column of the table the change
+     * is about: that is the column this view's rows were computed from, and 
the names are matched
+     * case-insensitively because a name is what moves. The other is a column 
the query reaches across a
+     * scope boundary -- the plan records those on the Apply that stands for 
the subquery, whose correlation
+     * slots are the outer columns its right side reads -- because such a name 
is the scopes' to answer for
+     * rather than the query's: the nearest column to the reference answers 
for it, so a column the change
+     * takes away from a scope inside leaves the name to one outside, and a 
column it gives to a scope inside
+     * takes the name over. A name reached with the qualifier of another table 
inside the query's own scope
+     * is neither: no later change can move it, so one to a column it does not 
name is one this view's rows
+     * do not depend on.
+     */
+    private static boolean reachesAnyColumnOf(Plan plan, BaseTableInfo 
baseTableInfo, Set<String> columnNames) {
+        if (plan == null) {
+            // A query whose plan was not kept is one this cannot be answered 
about, and "it does" is the
+            // answer that keeps the view safe.
+            return true;
+        }
+        Set<String> names = Sets.newTreeSet(String.CASE_INSENSITIVE_ORDER);
+        names.addAll(columnNames);
+        LineageInfo lineage = LineageInfoExtractor.extractLineageInfo(plan);
+        for (SetMultimap<?, Expression> byType : 
lineage.getDirectLineageMap().values()) {
+            if (reachesAnyColumn(byType.values(), names, baseTableInfo)) {
+                return true;
+            }
+        }
+        // The dataset predicates once, not once per output column: the 
per-output copy of them the lineage
+        // also offers holds the same expressions for every column the query 
produces, and scanning it would
+        // visit each of them once per column.
+        if (reachesAnyColumn(lineage.getDatasetIndirectLineageMap().values(), 
names, baseTableInfo)) {

Review Comment:
   Agreed, and this one is not fixed here either: the dataset lineage is what 
the view's own columns are read from, and a CTE producer the result never 
consumes is read by the same scan because the analysed plan keeps it under the 
anchor. Restricting that scan means walking the plan for what the result 
reaches -- skipping the producers no consumer reads -- which is a change to how 
this check traverses the plan rather than a name it matches, so it should land 
on its own.
   



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