Sort collation implemented, added ExplainIT

Signed-off-by: Selina Song <[email protected]>

Author: Selina Song

integ-test/src/test/java/org/opensearch/sql/calcite/remote/CalciteExplainIT.java

@@ -219,33 +219,18 @@ public void testExplainWithReverse() throws IOException {
 
   @Test
   public void testExplainWithReversePushdown() throws IOException {
-    // Test with a sort operation that should use the reverse pushdown optimization
-    String result =
-        executeWithReplace(
-            "explain source=opensearch-sql_test_index_account | sort - age | reverse");
-
-    // Verify that the plan contains a LogicalSort with ascending direction (reversed from DESC)
-    assertTrue(result.contains("LogicalSort"));
-    assertTrue(result.contains("dir0=[ASC]"));
-    
-    // Verify that ROW_NUMBER is NOT used (since we're using the collation-based optimization)
-    assertFalse(result.contains("ROW_NUMBER()"));
+    String query = "source=opensearch-sql_test_index_account | sort - age | reverse";
+    var result = explainQueryToString(query);
+    String expected = loadFromFile("expectedOutput/calcite/explain_reverse_pushdown_single.json");
+    assertJsonEqualsIgnoreId(expected, result);
   }
 
   @Test
   public void testExplainWithReversePushdownMultipleFields() throws IOException {
-    // Test with multiple sort fields that should use the reverse pushdown optimization
-    String result =
-        executeWithReplace(
-            "explain source=opensearch-sql_test_index_account | sort - age, + firstname | reverse");
-
-    // Verify that the plan contains a LogicalSort with reversed directions
-    assertTrue(result.contains("LogicalSort"));
-    assertTrue(result.contains("dir0=[ASC]")); // age was DESC, now ASC
-    assertTrue(result.contains("dir1=[DESC]")); // firstname was ASC, now DESC
-    
-    // Verify that ROW_NUMBER is NOT used (since we're using the collation-based optimization)
-    assertFalse(result.contains("ROW_NUMBER()"));
+    String query = "source=opensearch-sql_test_index_account | sort - age, + firstname | reverse";
+    var result = explainQueryToString(query);
+    String expected = loadFromFile("expectedOutput/calcite/explain_reverse_pushdown_multiple.json");
+    assertJsonEqualsIgnoreId(expected, result);
   }
 
   @Test

integ-test/src/test/resources/expectedOutput/calcite/explain_reverse_pushdown_multiple.json

@@ -0,0 +1,6 @@
+{
+  "calcite": {
+    "logical": "LogicalSystemLimit(sort0=[$8], sort1=[$1], dir0=[ASC], dir1=[DESC], fetch=[10000], type=[QUERY_SIZE_LIMIT])\n  LogicalProject(account_number=[$0], firstname=[$1], address=[$2], balance=[$3], gender=[$4], city=[$5], employer=[$6], state=[$7], age=[$8], email=[$9], lastname=[$10])\n    LogicalSort(sort0=[$8], sort1=[$1], dir0=[ASC], dir1=[DESC])\n      LogicalSort(sort0=[$8], sort1=[$1], dir0=[DESC-nulls-last], dir1=[ASC-nulls-first])\n        CalciteLogicalIndexScan(table=[[OpenSearch, opensearch-sql_test_index_account]])\n",
+    "physical": "CalciteEnumerableIndexScan(table=[[OpenSearch, opensearch-sql_test_index_account]], PushDownContext=[[PROJECT->[account_number, firstname, address, balance, gender, city, employer, state, age, email, lastname], SORT->[{\n  \"age\" : {\n    \"order\" : \"asc\",\n    \"missing\" : \"_last\"\n  }\n}, {\n  \"firstname.keyword\" : {\n    \"order\" : \"desc\",\n    \"missing\" : \"_first\"\n  }\n}], LIMIT->10000], OpenSearchRequestBuilder(sourceBuilder={\"from\":0,\"size\":10000,\"timeout\":\"1m\",\"_source\":{\"includes\":[\"account_number\",\"firstname\",\"address\",\"balance\",\"gender\",\"city\",\"employer\",\"state\",\"age\",\"email\",\"lastname\"],\"excludes\":[]},\"sort\":[{\"age\":{\"order\":\"asc\",\"missing\":\"_last\"}},{\"firstname.keyword\":{\"order\":\"desc\",\"missing\":\"_first\"}}]}, requestedTotalSize=10000, pageSize=null, startFrom=0)])\n"
+  }
+}

integ-test/src/test/resources/expectedOutput/calcite/explain_reverse_pushdown_single.json

@@ -0,0 +1,6 @@
+{
+  "calcite": {
+    "logical": "LogicalSystemLimit(sort0=[$8], dir0=[ASC], fetch=[10000], type=[QUERY_SIZE_LIMIT])\n  LogicalProject(account_number=[$0], firstname=[$1], address=[$2], balance=[$3], gender=[$4], city=[$5], employer=[$6], state=[$7], age=[$8], email=[$9], lastname=[$10])\n    LogicalSort(sort0=[$8], dir0=[ASC])\n      LogicalSort(sort0=[$8], dir0=[DESC-nulls-last])\n        CalciteLogicalIndexScan(table=[[OpenSearch, opensearch-sql_test_index_account]])\n",
+    "physical": "CalciteEnumerableIndexScan(table=[[OpenSearch, opensearch-sql_test_index_account]], PushDownContext=[[PROJECT->[account_number, firstname, address, balance, gender, city, employer, state, age, email, lastname], SORT->[{\n  \"age\" : {\n    \"order\" : \"asc\",\n    \"missing\" : \"_last\"\n  }\n}], LIMIT->10000], OpenSearchRequestBuilder(sourceBuilder={\"from\":0,\"size\":10000,\"timeout\":\"1m\",\"_source\":{\"includes\":[\"account_number\",\"firstname\",\"address\",\"balance\",\"gender\",\"city\",\"employer\",\"state\",\"age\",\"email\",\"lastname\"],\"excludes\":[]},\"sort\":[{\"age\":{\"order\":\"asc\",\"missing\":\"_last\"}}]}, requestedTotalSize=10000, pageSize=null, startFrom=0)])\n"
+  }
+}