update capability

Author: fang-xing-esql

x-pack/plugin/esql/qa/server/src/main/java/org/elasticsearch/xpack/esql/qa/rest/RestEsqlTestCase.java

@@ -996,8 +996,8 @@ private void validateResultsOfDoubleParametersForIdentifiers(RequestObjectBuilde
 
     public void testMultipleBatchesWithLookupJoin() throws IOException {
         assumeTrue(
-            "Requires new null alias ids for join with multiple batches",
-            EsqlCapabilities.Cap.REPLACE_MISSING_FIELD_WITH_NULL_NEW_ALIAS_ID_FOR_JOIN_AND_MULTIPLE_BATCHES.isEnabled()
+            "Makes numberOfChannels consistent with layout map for join with multiple batches",
+            EsqlCapabilities.Cap.MAKE_NUMBER_OF_CHANNELS_CONSISTENT_WITH_LAYOUT.isEnabled()
         );
         // Create more than 10 indices to trigger multiple batches of data node execution.
         // The sort field should be missing on some indices to reproduce NullPointerException caused by duplicated items in layout

x-pack/plugin/esql/qa/testFixtures/src/main/resources/lookup-join.csv-spec

@@ -1456,7 +1456,7 @@ emp_no:integer | language_code:integer | language_name:keyword
 multipleBatchesWithSort
 required_capability: join_lookup_v12
 required_capability: remove_redundant_sort
-required_capability: replace_missing_field_with_null_new_alias_id_for_join_and_multiple_batches
+required_capability: make_number_of_channels_consistent_with_layout
 
 from *
 | rename city.country.continent.planet.name as message
@@ -1473,7 +1473,7 @@ language_code:integer
 multipleBatchesWithMvExpand
 required_capability: join_lookup_v12
 required_capability: remove_redundant_sort
-required_capability: replace_missing_field_with_null_new_alias_id_for_join_and_multiple_batches
+required_capability: make_number_of_channels_consistent_with_layout
 
 from *
 | rename city.country.continent.planet.name as message
@@ -1491,7 +1491,7 @@ birth_date:datetime      |language_code:integer
 multipleBatchesWithAggregate1
 required_capability: join_lookup_v12
 required_capability: remove_redundant_sort
-required_capability: replace_missing_field_with_null_new_alias_id_for_join_and_multiple_batches
+required_capability: make_number_of_channels_consistent_with_layout
 
 from *
 | rename city.country.continent.planet.name as message
@@ -1507,7 +1507,7 @@ x:datetime               |y:integer
 multipleBatchesWithAggregate2
 required_capability: join_lookup_v12
 required_capability: remove_redundant_sort
-required_capability: replace_missing_field_with_null_new_alias_id_for_join_and_multiple_batches
+required_capability: make_number_of_channels_consistent_with_layout
 
 from *
 | rename city.country.continent.planet.name as message
@@ -1525,7 +1525,7 @@ null       |1
 multipleBatchesWithAggregate3
 required_capability: join_lookup_v12
 required_capability: remove_redundant_sort
-required_capability: replace_missing_field_with_null_new_alias_id_for_join_and_multiple_batches
+required_capability: make_number_of_channels_consistent_with_layout
 
 from *
 | rename city.country.continent.planet.name as message

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/action/EsqlCapabilities.java

@@ -930,9 +930,9 @@ public enum Cap {
         INDEX_COMPONENT_SELECTORS(DataStream.isFailureStoreFeatureFlagEnabled()),
 
         /**
-         * Create null alias with new id in ReplaceMissingFieldWithNull when there is lookup join with multiple batches.
+         * Make numberOfChannels consistent with layout in DefaultLayout by removing duplicated ChannelSet.
          */
-        REPLACE_MISSING_FIELD_WITH_NULL_NEW_ALIAS_ID_FOR_JOIN_AND_MULTIPLE_BATCHES;
+        MAKE_NUMBER_OF_CHANNELS_CONSISTENT_WITH_LAYOUT;
 
         private final boolean enabled;
 

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/planner/Layout.java

@@ -111,6 +111,10 @@ public Layout build() {
                 int channel = 0;
                 for (NameId id : set.nameIds) {
                     if (layout.containsKey(id)) {
+                        // If a NameId already exists in the map, do not increase the numberOfChannels, it can cause inverse() to create
+                        // a null in the list of channels, and NullPointerException when build() is called.
+                        // TODO avoid adding duplicated attributes with the same id in the plan, ReplaceMissingFieldWithNull may add nulls
+                        // with the same ids as the missing field ids.
                         continue;
                     }
                     if (createNewChannel) {