yujun777 commented on code in PR #68646:
URL: https://github.com/apache/doris/pull/68646#discussion_r4219511031
##########
fe/fe-core/src/main/java/org/apache/doris/mtmv/MTMVRelationManager.java:
##########
@@ -349,34 +360,221 @@ 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)) {
+ return true;
+ }
+ if (reachesAnyColumnOfASubquery(plan, names, baseTableInfo)) {
+ return true;
+ }
+ return reachesAnyColumnAcrossScopes(plan, lineage, names,
baseTableInfo);
+ }
+
+ /** Whether this slot is a column of this table, through whatever views
stand between the two. */
+ private static boolean isColumnOf(Slot slot, BaseTableInfo baseTableInfo) {
+ if (!(slot instanceof SlotReference)) {
+ return false;
+ }
+ return ((SlotReference) slot).getOriginalTable()
+ .map(table -> new BaseTableInfo(table).equals(baseTableInfo))
+ .orElse(false);
+ }
+
+ /**
+ * Whether a name the change is about is answered for inside a subquery,
out of that subquery's own
+ * scope.
+ *
+ * <p>This is the one place a name can move without any column the view
produces depending on it: the
+ * scope of a subquery is internal, so which column answers for a name
there changes what the query
+ * returns -- a row, or none -- while every column of the view stays the
one it was. The lineage of the
+ * view's columns does not reach it, so the scope the subquery became is
read here, expression by
+ * expression, the way the lineage is read for the view's own.
+ *
+ * <p>Two things are read. One is a value the subquery itself names -- an
expression of its own under one
+ * of these names, rather than a column of a table -- because that is what
a name the change takes away
+ * falls back to, and it decides the rows whether the subquery is a
predicate or a value. It is read only
+ * where the table the change is about is one that subquery reads: what a
name falls back to is what the
+ * scope that answered for it holds, so a scope that does not read the
table holds nothing for the name
+ * and one of its own is one the change never reached. The other is a
column of the table the change is
+ * about, which decides the rows only when the subquery's output is one
the query reads: an EXISTS tests
+ * the rows of its subquery and not what it projects, so a name it
projects and never compares is one
+ * this view's rows do not depend on.
+ *
+ * <p>Each scope is read on its own. A subquery inside one of these is a
scope of its own, and it is
+ * judged where it is read and not as a part of its enclosing one: its
projection is held only where
+ * that scope's own output is read, so an EXISTS inside an IN is still not
compared by the IN.
+ */
+ private static boolean reachesAnyColumnOfASubquery(Plan plan, Set<String>
names,
+ BaseTableInfo baseTableInfo) {
+ for (LogicalApply<?, ?> apply :
plan.<LogicalApply>collectToList(LogicalApply.class::isInstance)) {
+ List<Plan> itsOwnScope = ownScopeOf(apply);
+ boolean outputDecidesRows = !apply.isExist();
+ boolean isOneOfItsTables = readsAnyTableOf(itsOwnScope,
baseTableInfo);
+ for (Plan node : itsOwnScope) {
+ for (Expression expression : node.getExpressions()) {
+ if ((isOneOfItsTables &&
readsAnyNameTheSubqueryAnswersFor(expression, names))
+ || (outputDecidesRows &&
reachesAnyColumn(expression, names, baseTableInfo))) {
+ return true;
+ }
+ }
+ }
+ }
+ return false;
+ }
+
+ /**
+ * The nodes of a subquery that belong to the scope this Apply stands for:
its right side, with the
+ * right side of every subquery nested in it left out.
+ *
+ * <p>A nested Apply is a scope of its own and is read as one, so its
right side belongs to that read
+ * rather than to this one; the relation it is asked about is the
enclosing scope's own and stays.
+ */
+ private static List<Plan> ownScopeOf(LogicalApply<?, ?> apply) {
+ List<Plan> itsOwnScope = Lists.newArrayList();
+ collectItsOwnScope((Plan) apply.right(), itsOwnScope);
+ return itsOwnScope;
+ }
+
+ private static void collectItsOwnScope(Plan node, List<Plan> itsOwnScope) {
+ itsOwnScope.add(node);
+ if (node instanceof LogicalApply) {
+ collectItsOwnScope(((LogicalApply<?, ?>) node).left(),
itsOwnScope);
+ return;
+ }
+ for (Plan child : node.children()) {
+ collectItsOwnScope(child, itsOwnScope);
+ }
+ }
+
+ /** Whether one of these nodes reads this table, through whatever views
stand between the two. */
+ private static boolean readsAnyTableOf(List<Plan> itsOwnScope,
BaseTableInfo baseTableInfo) {
+ return itsOwnScope.stream().anyMatch(node -> node instanceof
LogicalCatalogRelation
+ && new BaseTableInfo(((LogicalCatalogRelation)
node).getTable()).equals(baseTableInfo));
+ }
+
+ /**
+ * Whether this expression reads a value the subquery answers for itself,
under one of these names: a
+ * slot of the subquery's own -- an alias or a value it computed -- rather
than a column of a table.
+ *
+ * <p>Read rather than merely named, because an expression of the subquery
carrying one of these names
+ * says nothing on its own: a subquery that names a `flag` of its own
while no reference in it resolves
+ * to that name is one whose rows the change cannot reach, and one that
reads the name it names is where
+ * a reference that answered for the changed column falls back to.
+ */
+ private static boolean readsAnyNameTheSubqueryAnswersFor(Expression
expression, Set<String> names) {
+ for (Slot slot : expression.getInputSlots()) {
+ if (names.contains(slot.getName()) && !isColumnOfATable(slot)) {
+ return true;
+ }
+ }
+ return false;
+ }
+
+ /** Whether this slot is a column of some table, or a value produced
inside the query. */
+ private static boolean isColumnOfATable(Slot slot) {
+ return slot instanceof SlotReference && ((SlotReference)
slot).getOriginalTable().isPresent();
+ }
+
+ /** Whether this expression reads a column of one of these names from this
table. */
+ private static boolean reachesAnyColumn(Expression expression, Set<String>
names,
+ BaseTableInfo baseTableInfo) {
+ return reachesAnyColumn(ImmutableList.of(expression), names,
baseTableInfo);
+ }
+
+ /** Whether any of these expressions reads a column of one of these names
from this table. */
+ private static boolean reachesAnyColumn(Collection<? extends Expression>
expressions, Set<String> names,
+ BaseTableInfo baseTableInfo) {
+ for (Expression expression : expressions) {
+ for (Slot slot : expression.getInputSlots()) {
Review Comment:
Confirmed as over-invalidation, and not fixed here. Measured: adding
`changed_t.flag` invalidates the view and drops its rewrite snapshot, while
`d.flag` goes on reading `c.x` and every row of the query is the same.
You are right about the cause: the column branch matches the slot's visible
name against the changed name, and an alias renames the slot while keeping the
column it came from. Comparing the original column is the better identity, and
it may well be a narrowing rather than a trade -- but it decides which slots
this branch recognises for the alias shapes the threads here keep producing, so
it wants its own cases rather than a line changed inside this one.
##########
fe/fe-core/src/main/java/org/apache/doris/mtmv/MTMVRelationManager.java:
##########
@@ -349,34 +360,221 @@ 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)) {
+ return true;
+ }
+ if (reachesAnyColumnOfASubquery(plan, names, baseTableInfo)) {
+ return true;
+ }
+ return reachesAnyColumnAcrossScopes(plan, lineage, names,
baseTableInfo);
+ }
+
+ /** Whether this slot is a column of this table, through whatever views
stand between the two. */
+ private static boolean isColumnOf(Slot slot, BaseTableInfo baseTableInfo) {
+ if (!(slot instanceof SlotReference)) {
+ return false;
+ }
+ return ((SlotReference) slot).getOriginalTable()
+ .map(table -> new BaseTableInfo(table).equals(baseTableInfo))
+ .orElse(false);
+ }
+
+ /**
+ * Whether a name the change is about is answered for inside a subquery,
out of that subquery's own
+ * scope.
+ *
+ * <p>This is the one place a name can move without any column the view
produces depending on it: the
+ * scope of a subquery is internal, so which column answers for a name
there changes what the query
+ * returns -- a row, or none -- while every column of the view stays the
one it was. The lineage of the
+ * view's columns does not reach it, so the scope the subquery became is
read here, expression by
+ * expression, the way the lineage is read for the view's own.
+ *
+ * <p>Two things are read. One is a value the subquery itself names -- an
expression of its own under one
+ * of these names, rather than a column of a table -- because that is what
a name the change takes away
+ * falls back to, and it decides the rows whether the subquery is a
predicate or a value. It is read only
+ * where the table the change is about is one that subquery reads: what a
name falls back to is what the
+ * scope that answered for it holds, so a scope that does not read the
table holds nothing for the name
+ * and one of its own is one the change never reached. The other is a
column of the table the change is
+ * about, which decides the rows only when the subquery's output is one
the query reads: an EXISTS tests
+ * the rows of its subquery and not what it projects, so a name it
projects and never compares is one
+ * this view's rows do not depend on.
+ *
+ * <p>Each scope is read on its own. A subquery inside one of these is a
scope of its own, and it is
+ * judged where it is read and not as a part of its enclosing one: its
projection is held only where
+ * that scope's own output is read, so an EXISTS inside an IN is still not
compared by the IN.
+ */
+ private static boolean reachesAnyColumnOfASubquery(Plan plan, Set<String>
names,
+ BaseTableInfo baseTableInfo) {
+ for (LogicalApply<?, ?> apply :
plan.<LogicalApply>collectToList(LogicalApply.class::isInstance)) {
+ List<Plan> itsOwnScope = ownScopeOf(apply);
+ boolean outputDecidesRows = !apply.isExist();
+ boolean isOneOfItsTables = readsAnyTableOf(itsOwnScope,
baseTableInfo);
+ for (Plan node : itsOwnScope) {
+ for (Expression expression : node.getExpressions()) {
+ if ((isOneOfItsTables &&
readsAnyNameTheSubqueryAnswersFor(expression, names))
+ || (outputDecidesRows &&
reachesAnyColumn(expression, names, baseTableInfo))) {
+ return true;
+ }
+ }
+ }
+ }
+ return false;
+ }
+
+ /**
+ * The nodes of a subquery that belong to the scope this Apply stands for:
its right side, with the
+ * right side of every subquery nested in it left out.
+ *
+ * <p>A nested Apply is a scope of its own and is read as one, so its
right side belongs to that read
+ * rather than to this one; the relation it is asked about is the
enclosing scope's own and stays.
+ */
+ private static List<Plan> ownScopeOf(LogicalApply<?, ?> apply) {
+ List<Plan> itsOwnScope = Lists.newArrayList();
+ collectItsOwnScope((Plan) apply.right(), itsOwnScope);
+ return itsOwnScope;
+ }
+
+ private static void collectItsOwnScope(Plan node, List<Plan> itsOwnScope) {
+ itsOwnScope.add(node);
+ if (node instanceof LogicalApply) {
+ collectItsOwnScope(((LogicalApply<?, ?>) node).left(),
itsOwnScope);
+ return;
+ }
+ for (Plan child : node.children()) {
+ collectItsOwnScope(child, itsOwnScope);
+ }
+ }
+
+ /** Whether one of these nodes reads this table, through whatever views
stand between the two. */
+ private static boolean readsAnyTableOf(List<Plan> itsOwnScope,
BaseTableInfo baseTableInfo) {
+ return itsOwnScope.stream().anyMatch(node -> node instanceof
LogicalCatalogRelation
+ && new BaseTableInfo(((LogicalCatalogRelation)
node).getTable()).equals(baseTableInfo));
+ }
+
+ /**
+ * Whether this expression reads a value the subquery answers for itself,
under one of these names: a
+ * slot of the subquery's own -- an alias or a value it computed -- rather
than a column of a table.
+ *
+ * <p>Read rather than merely named, because an expression of the subquery
carrying one of these names
+ * says nothing on its own: a subquery that names a `flag` of its own
while no reference in it resolves
+ * to that name is one whose rows the change cannot reach, and one that
reads the name it names is where
+ * a reference that answered for the changed column falls back to.
+ */
+ private static boolean readsAnyNameTheSubqueryAnswersFor(Expression
expression, Set<String> names) {
+ for (Slot slot : expression.getInputSlots()) {
+ if (names.contains(slot.getName()) && !isColumnOfATable(slot)) {
+ return true;
+ }
+ }
+ return false;
+ }
+
+ /** Whether this slot is a column of some table, or a value produced
inside the query. */
+ private static boolean isColumnOfATable(Slot slot) {
+ return slot instanceof SlotReference && ((SlotReference)
slot).getOriginalTable().isPresent();
+ }
+
+ /** Whether this expression reads a column of one of these names from this
table. */
+ private static boolean reachesAnyColumn(Expression expression, Set<String>
names,
+ BaseTableInfo baseTableInfo) {
+ return reachesAnyColumn(ImmutableList.of(expression), names,
baseTableInfo);
+ }
+
+ /** Whether any of these expressions reads a column of one of these names
from this table. */
+ private static boolean reachesAnyColumn(Collection<? extends Expression>
expressions, Set<String> names,
+ BaseTableInfo baseTableInfo) {
+ for (Expression expression : expressions) {
+ for (Slot slot : expression.getInputSlots()) {
+ if (names.contains(slot.getName()) && isColumnOf(slot,
baseTableInfo)) {
+ return true;
+ }
+ }
+ }
+ return false;
+ }
+
+ /**
+ * Whether the query resolves a column of one of these names across a
scope boundary, which is a name
+ * the change can move whatever the query writes it against.
+ */
+ private static boolean reachesAnyColumnAcrossScopes(Plan plan, LineageInfo
lineage, Set<String> names,
+ BaseTableInfo baseTableInfo) {
+ // A name is only one the change can move if the table it is about is
one the query reads at all.
Review Comment:
Confirmed as over-invalidation, and not fixed here. Measured: the view is
invalidated and loses its snapshot, while the second subquery's `flag` goes on
reading `o.flag` and every row of the query is the same.
The cause is the branch rather than a name: this one asks whether the query
resolves any of these names across a scope boundary and whether the changed
table is one the query reads anywhere, without asking whether that particular
Apply is one the changed table could enter. The per-Apply read this PR added
already asks the second question for the subquery's own names, so the same
restriction is a candidate for the correlation branch too -- but the branch is
also what catches a name that stopped being answered inside a subquery and
started being answered outside it, and I have not worked through which
correlations of a scope remain the change's when that scope is restricted. It
wants its own change rather than a guess here.
##########
fe/fe-core/src/main/java/org/apache/doris/mtmv/MTMVRelationManager.java:
##########
@@ -349,34 +360,221 @@ 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)) {
+ return true;
+ }
+ if (reachesAnyColumnOfASubquery(plan, names, baseTableInfo)) {
+ return true;
+ }
+ return reachesAnyColumnAcrossScopes(plan, lineage, names,
baseTableInfo);
+ }
+
+ /** Whether this slot is a column of this table, through whatever views
stand between the two. */
+ private static boolean isColumnOf(Slot slot, BaseTableInfo baseTableInfo) {
+ if (!(slot instanceof SlotReference)) {
+ return false;
+ }
+ return ((SlotReference) slot).getOriginalTable()
+ .map(table -> new BaseTableInfo(table).equals(baseTableInfo))
+ .orElse(false);
+ }
+
+ /**
+ * Whether a name the change is about is answered for inside a subquery,
out of that subquery's own
+ * scope.
+ *
+ * <p>This is the one place a name can move without any column the view
produces depending on it: the
+ * scope of a subquery is internal, so which column answers for a name
there changes what the query
+ * returns -- a row, or none -- while every column of the view stays the
one it was. The lineage of the
+ * view's columns does not reach it, so the scope the subquery became is
read here, expression by
+ * expression, the way the lineage is read for the view's own.
+ *
+ * <p>Two things are read. One is a value the subquery itself names -- an
expression of its own under one
+ * of these names, rather than a column of a table -- because that is what
a name the change takes away
+ * falls back to, and it decides the rows whether the subquery is a
predicate or a value. It is read only
+ * where the table the change is about is one that subquery reads: what a
name falls back to is what the
+ * scope that answered for it holds, so a scope that does not read the
table holds nothing for the name
+ * and one of its own is one the change never reached. The other is a
column of the table the change is
+ * about, which decides the rows only when the subquery's output is one
the query reads: an EXISTS tests
+ * the rows of its subquery and not what it projects, so a name it
projects and never compares is one
+ * this view's rows do not depend on.
+ *
+ * <p>Each scope is read on its own. A subquery inside one of these is a
scope of its own, and it is
+ * judged where it is read and not as a part of its enclosing one: its
projection is held only where
+ * that scope's own output is read, so an EXISTS inside an IN is still not
compared by the IN.
+ */
+ private static boolean reachesAnyColumnOfASubquery(Plan plan, Set<String>
names,
+ BaseTableInfo baseTableInfo) {
+ for (LogicalApply<?, ?> apply :
plan.<LogicalApply>collectToList(LogicalApply.class::isInstance)) {
+ List<Plan> itsOwnScope = ownScopeOf(apply);
+ boolean outputDecidesRows = !apply.isExist();
+ boolean isOneOfItsTables = readsAnyTableOf(itsOwnScope,
baseTableInfo);
+ for (Plan node : itsOwnScope) {
+ for (Expression expression : node.getExpressions()) {
+ if ((isOneOfItsTables &&
readsAnyNameTheSubqueryAnswersFor(expression, names))
+ || (outputDecidesRows &&
reachesAnyColumn(expression, names, baseTableInfo))) {
+ return true;
+ }
+ }
+ }
+ }
+ return false;
+ }
+
+ /**
+ * The nodes of a subquery that belong to the scope this Apply stands for:
its right side, with the
+ * right side of every subquery nested in it left out.
+ *
+ * <p>A nested Apply is a scope of its own and is read as one, so its
right side belongs to that read
+ * rather than to this one; the relation it is asked about is the
enclosing scope's own and stays.
+ */
+ private static List<Plan> ownScopeOf(LogicalApply<?, ?> apply) {
+ List<Plan> itsOwnScope = Lists.newArrayList();
+ collectItsOwnScope((Plan) apply.right(), itsOwnScope);
+ return itsOwnScope;
+ }
+
+ private static void collectItsOwnScope(Plan node, List<Plan> itsOwnScope) {
+ itsOwnScope.add(node);
+ if (node instanceof LogicalApply) {
+ collectItsOwnScope(((LogicalApply<?, ?>) node).left(),
itsOwnScope);
+ return;
+ }
+ for (Plan child : node.children()) {
+ collectItsOwnScope(child, itsOwnScope);
+ }
+ }
+
+ /** Whether one of these nodes reads this table, through whatever views
stand between the two. */
+ private static boolean readsAnyTableOf(List<Plan> itsOwnScope,
BaseTableInfo baseTableInfo) {
+ return itsOwnScope.stream().anyMatch(node -> node instanceof
LogicalCatalogRelation
+ && new BaseTableInfo(((LogicalCatalogRelation)
node).getTable()).equals(baseTableInfo));
+ }
+
+ /**
+ * Whether this expression reads a value the subquery answers for itself,
under one of these names: a
+ * slot of the subquery's own -- an alias or a value it computed -- rather
than a column of a table.
+ *
+ * <p>Read rather than merely named, because an expression of the subquery
carrying one of these names
+ * says nothing on its own: a subquery that names a `flag` of its own
while no reference in it resolves
+ * to that name is one whose rows the change cannot reach, and one that
reads the name it names is where
+ * a reference that answered for the changed column falls back to.
+ */
+ private static boolean readsAnyNameTheSubqueryAnswersFor(Expression
expression, Set<String> names) {
+ for (Slot slot : expression.getInputSlots()) {
+ if (names.contains(slot.getName()) && !isColumnOfATable(slot)) {
+ return true;
+ }
+ }
+ return false;
+ }
+
+ /** Whether this slot is a column of some table, or a value produced
inside the query. */
+ private static boolean isColumnOfATable(Slot slot) {
+ return slot instanceof SlotReference && ((SlotReference)
slot).getOriginalTable().isPresent();
+ }
+
+ /** Whether this expression reads a column of one of these names from this
table. */
+ private static boolean reachesAnyColumn(Expression expression, Set<String>
names,
+ BaseTableInfo baseTableInfo) {
+ return reachesAnyColumn(ImmutableList.of(expression), names,
baseTableInfo);
+ }
+
+ /** Whether any of these expressions reads a column of one of these names
from this table. */
+ private static boolean reachesAnyColumn(Collection<? extends Expression>
expressions, Set<String> names,
+ BaseTableInfo baseTableInfo) {
+ for (Expression expression : expressions) {
+ for (Slot slot : expression.getInputSlots()) {
+ if (names.contains(slot.getName()) && isColumnOf(slot,
baseTableInfo)) {
+ return true;
+ }
+ }
+ }
+ return false;
+ }
+
+ /**
+ * Whether the query resolves a column of one of these names across a
scope boundary, which is a name
+ * the change can move whatever the query writes it against.
+ */
+ private static boolean reachesAnyColumnAcrossScopes(Plan plan, LineageInfo
lineage, Set<String> names,
+ BaseTableInfo baseTableInfo) {
+ // A name is only one the change can move if the table it is about is
one the query reads at all.
+ boolean isOneOfItsTables = lineage.getTableLineageSet().stream()
+ .anyMatch(table -> new
BaseTableInfo(table).equals(baseTableInfo));
+ if (!isOneOfItsTables) {
+ return false;
+ }
Review Comment:
Confirmed as over-invalidation, and not fixed here. Measured: the view is
invalidated and loses its snapshot, while the projection's name goes on reading
the outer table's column and every row is the same.
The correlation is read here without asking what the subquery does with it,
and an EXISTS is the case where that matters most: it tests the rows of its
subquery, so a name only projected is not a name it compares. The per-Apply
read skips exactly that for a subquery's own scope, so the two are inconsistent
-- but the correlation branch also has to keep the correlations that decide an
EXISTS (a name that moved *into* the subquery's filters), and telling those
apart is the same output-versus-predicate question rather than a scope
question. Not approximated here.
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