SQL: Fix issue with complex expression as args of PERCENTILE/_RANK (#37102)

When the arguements of PERCENTILE and PERCENTILE_RANK can be folded,
the `ConstantFolding` rule kicks in and calls the `replaceChildren()`
method on `InnerAggregate` which is created from the aggregation rules
of the `Optimizerz. `InnerAggregate` in turn, cannot implement the method
as the logic of creating a new `InnerAggregate` instance from a list of
`Expression`s resides in the Optimizer. So, instead, `ConstantFolding`
should be applied before any of the aggregations related rules.

Fixes: #37099

Author: matriv

x-pack/plugin/sql/qa/src/main/resources/agg.csv-spec

@@ -3,7 +3,7 @@
 //
 
 singlePercentileWithoutComma
-SELECT gender, PERCENTILE(emp_no, 97) p1 FROM test_emp GROUP BY gender;
+SELECT gender, PERCENTILE(emp_no, 90 + 7) p1 FROM test_emp GROUP BY gender;
 
 gender:s             | p1:d
 null                 |10019.0           
@@ -48,7 +48,7 @@ M                    |10084.349             |10093.502
 ;
 
 percentileRank
-SELECT gender, PERCENTILE_RANK(emp_no, 10025) rank FROM test_emp GROUP BY gender;
+SELECT gender, PERCENTILE_RANK(emp_no, 10000 + 25) rank FROM test_emp GROUP BY gender;
 
 gender:s             | rank:d
 null                 |100.0             

x-pack/plugin/sql/src/main/java/org/elasticsearch/xpack/sql/optimizer/Optimizer.java

@@ -159,7 +159,7 @@ protected Iterable<RuleExecutor<LogicalPlan>.Batch> batches() {
         Batch label = new Batch("Set as Optimized", Limiter.ONCE,
                 new SetAsOptimized());
 
-        return Arrays.asList(aggregate, operators, local, label);
+        return Arrays.asList(operators, aggregate, local, label);
     }
 
 

x-pack/plugin/sql/src/test/java/org/elasticsearch/xpack/sql/planner/QueryFolderTests.java

@@ -12,6 +12,7 @@
 import org.elasticsearch.xpack.sql.analysis.index.EsIndex;
 import org.elasticsearch.xpack.sql.analysis.index.IndexResolution;
 import org.elasticsearch.xpack.sql.expression.function.FunctionRegistry;
+import org.elasticsearch.xpack.sql.expression.function.aggregate.AggregateFunctionAttribute;
 import org.elasticsearch.xpack.sql.optimizer.Optimizer;
 import org.elasticsearch.xpack.sql.parser.SqlParser;
 import org.elasticsearch.xpack.sql.plan.physical.EsQueryExec;
@@ -316,4 +317,24 @@ public void testConcatIsNotFoldedForNull() {
         assertEquals(1, ee.output().size());
         assertThat(ee.output().get(0).toString(), startsWith("keyword{f}#"));
     }
+
+    public void testFoldingOfPercentileSecondArgument() {
+        PhysicalPlan p = plan("SELECT PERCENTILE(int, 1 + 2) FROM test");
+        assertEquals(EsQueryExec.class, p.getClass());
+        EsQueryExec ee = (EsQueryExec) p;
+        assertEquals(1, ee.output().size());
+        assertEquals(AggregateFunctionAttribute.class, ee.output().get(0).getClass());
+        AggregateFunctionAttribute afa = (AggregateFunctionAttribute) ee.output().get(0);
+        assertThat(afa.propertyPath(), endsWith("[3.0]"));
+    }
+
+    public void testFoldingOfPercentileRankSecondArgument() {
+        PhysicalPlan p = plan("SELECT PERCENTILE_RANK(int, 1 + 2) FROM test");
+        assertEquals(EsQueryExec.class, p.getClass());
+        EsQueryExec ee = (EsQueryExec) p;
+        assertEquals(1, ee.output().size());
+        assertEquals(AggregateFunctionAttribute.class, ee.output().get(0).getClass());
+        AggregateFunctionAttribute afa = (AggregateFunctionAttribute) ee.output().get(0);
+        assertThat(afa.propertyPath(), endsWith("[3.0]"));
+    }
 }