[FollowUp] Set 0 and negative value of subsearch.maxout as unlimited

core/src/main/java/org/opensearch/sql/calcite/CalciteRelNodeVisitor.java

@@ -1138,8 +1138,8 @@ private Optional<RexLiteral> extractAliasLiteral(RexNode node) {
   public RelNode visitJoin(Join node, CalcitePlanContext context) {
     List<UnresolvedPlan> children = node.getChildren();
     children.forEach(c -> analyze(c, context));
-    // add join.subsearch_maxout limit to subsearch side
-    if (context.sysLimit.joinSubsearchLimit() >= 0) {
+    // add join.subsearch_maxout limit to subsearch side, 0 and negative means unlimited.
+    if (context.sysLimit.joinSubsearchLimit() > 0) {
       PlanUtils.replaceTop(
           context.relBuilder,
           LogicalSystemLimit.create(

core/src/main/java/org/opensearch/sql/calcite/CalciteRexNodeVisitor.java

@@ -516,9 +516,8 @@ private RelNode resolveSubqueryPlan(
       context.setResolvingJoinCondition(false);
     }
     subquery.accept(planVisitor, context);
-
+    // add subsearch.maxout limit to exists-in subsearch, 0 and negative means unlimited
     if (context.sysLimit.subsearchLimit() > 0 && !(subqueryExpression instanceof ScalarSubquery)) {
-      // Add subsearch.maxout limit to exists-in subsearch:
       // Cannot add system limit to the top of subquery simply.
       // Instead, add system limit under the correlated conditions.
       SubsearchUtils.SystemLimitInsertionShuttle shuttle =
@@ -536,10 +535,6 @@ private RelNode resolveSubqueryPlan(
     }
     // pop the inner plan
     RelNode subqueryRel = context.relBuilder.build();
-    // if maxout = 0, return empty results
-    if (context.sysLimit.subsearchLimit() == 0) {
-      subqueryRel = context.relBuilder.values(subqueryRel.getRowType()).build();
-    }
     // clear the exists subquery resolving state
     // restore to the previous state
     if (isResolvingJoinConditionOuter) {

core/src/main/java/org/opensearch/sql/calcite/SysLimit.java

@@ -19,7 +19,7 @@ public static SysLimit fromSettings(Settings settings) {
   }
 
   /** No limitation on subsearch */
-  public static SysLimit UNLIMITED_SUBSEARCH = new SysLimit(10000, -1, -1);
+  public static SysLimit UNLIMITED_SUBSEARCH = new SysLimit(10000, 0, 0);
 
   /** For testing only */
   public static SysLimit DEFAULT = new SysLimit(10000, 10000, 50000);

docs/user/ppl/admin/settings.rst

@@ -290,7 +290,7 @@ plugins.ppl.subsearch.maxout
 Description
 -----------
 
-The size configures the maximum of rows to return from subsearch. The default value is: ``10000``. A value of ``-1`` indicates that the restriction is unlimited.
+The size configures the maximum of rows to return from subsearch. The default value is: ``10000``. A value of ``0`` indicates that the restriction is unlimited.
 
 Version
 -------
@@ -303,14 +303,14 @@ Change the subsearch.maxout to unlimited::
 
     sh$ curl -sS -H 'Content-Type: application/json' \
     ... -X PUT localhost:9200/_plugins/_query/settings \
-    ... -d '{"persistent" : {"plugins.ppl.subsearch.maxout" : "-1"}}'
+    ... -d '{"persistent" : {"plugins.ppl.subsearch.maxout" : "0"}}'
     {
       "acknowledged": true,
       "persistent": {
         "plugins": {
           "ppl": {
             "subsearch": {
-              "maxout": "-1"
+              "maxout": "0"
             }
           }
         }
@@ -324,7 +324,7 @@ plugins.ppl.join.subsearch_maxout
 Description
 -----------
 
-The size configures the maximum of rows from subsearch to join against. This configuration impacts ``join`` command. The default value is: ``50000``. A value of ``-1`` indicates that the restriction is unlimited.
+The size configures the maximum of rows from subsearch to join against. This configuration impacts ``join`` command. The default value is: ``50000``. A value of ``0`` indicates that the restriction is unlimited.
 
 Version
 -------

docs/user/ppl/cmd/join.rst

@@ -71,7 +71,7 @@ Result set::
 plugins.ppl.join.subsearch_maxout
 ---------------------------------
 
-The size configures the maximum of rows from subsearch to join against. The default value is: ``50000``. A value of ``-1`` indicates that the restriction is unlimited.
+The size configures the maximum of rows from subsearch to join against. The default value is: ``50000``. A value of ``0`` indicates that the restriction is unlimited.
 
 Change the join.subsearch_maxout to 5000::
 

docs/user/ppl/cmd/subquery.rst

@@ -73,13 +73,13 @@ Result set::
 plugins.ppl.subsearch.maxout
 ----------------------------
 
-The size configures the maximum of rows to return from subsearch. The default value is: ``10000``. A value of ``-1`` indicates that the restriction is unlimited.
+The size configures the maximum of rows to return from subsearch. The default value is: ``10000``. A value of ``0`` indicates that the restriction is unlimited.
 
 Change the subsearch.maxout to unlimited::
 
     sh$ curl -sS -H 'Content-Type: application/json' \
     ... -X PUT localhost:9200/_plugins/_query/settings \
-    ... -d '{"persistent" : {"plugins.ppl.subsearch.maxout" : "-1"}}'
+    ... -d '{"persistent" : {"plugins.ppl.subsearch.maxout" : "0"}}'
     {
       "acknowledged": true,
       "persistent": {

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

@@ -378,7 +378,7 @@ public void testSubsearchMaxOutUncorrelated() throws IOException {
   }
 
   @Test
-  public void testSubsearchMaxOutZero1() throws IOException {
+  public void testUncorrelatedSubsearchMaxOutZeroMeansUnlimited() throws IOException {
     setSubsearchMaxOut(0);
     JSONObject result =
         executeQuery(
@@ -390,24 +390,12 @@ public void testSubsearchMaxOutZero1() throws IOException {
                     + "| sort  - salary"
                     + "| fields id, name, salary",
                 TEST_INDEX_WORKER, TEST_INDEX_WORK_INFORMATION));
-    verifyNumOfRows(result, 0);
-
-    result =
-        executeQuery(
-            String.format(
-                "source = %s"
-                    + "| where not exists ["
-                    + "    source = %s | where name = 'Tom'"
-                    + "  ]"
-                    + "| sort  - salary"
-                    + "| fields id, name, salary",
-                TEST_INDEX_WORKER, TEST_INDEX_WORK_INFORMATION));
     verifyNumOfRows(result, 7);
     resetSubsearchMaxOut();
   }
 
   @Test
-  public void testSubsearchMaxOutZero2() throws IOException {
+  public void testCorrelatedSubsearchMaxOutZeroMeansUnlimited() throws IOException {
     setSubsearchMaxOut(0);
     JSONObject result =
         executeQuery(
@@ -419,7 +407,7 @@ public void testSubsearchMaxOutZero2() throws IOException {
                     + "| sort  - salary"
                     + "| fields id, name, salary",
                 TEST_INDEX_WORKER, TEST_INDEX_WORK_INFORMATION));
-    verifyNumOfRows(result, 0);
+    verifyNumOfRows(result, 5);
     result =
         executeQuery(
             String.format(
@@ -430,12 +418,12 @@ public void testSubsearchMaxOutZero2() throws IOException {
                     + "| sort  - salary"
                     + "| fields id, name, salary",
                 TEST_INDEX_WORKER, TEST_INDEX_WORK_INFORMATION));
-    verifyNumOfRows(result, 7);
+    verifyNumOfRows(result, 2);
     resetSubsearchMaxOut();
   }
 
   @Test
-  public void testSubsearchMaxOutUnlimited() throws IOException {
+  public void testSubsearchMaxOutNegativeMeansUnlimited() throws IOException {
     setSubsearchMaxOut(-1);
     JSONObject result =
         executeQuery(

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

@@ -403,7 +403,7 @@ public void testInCorrelatedSubqueryMaxOut() throws IOException {
   }
 
   @Test
-  public void testSubsearchMaxOutZero() throws IOException {
+  public void testSubsearchMaxOutZeroMeansUnlimited() throws IOException {
     setSubsearchMaxOut(0);
     JSONObject result =
         executeQuery(
@@ -416,7 +416,7 @@ public void testSubsearchMaxOutZero() throws IOException {
                     + "| fields id, name, salary",
                 TEST_INDEX_WORKER, TEST_INDEX_WORK_INFORMATION));
     verifySchema(result, schema("id", "int"), schema("name", "string"), schema("salary", "int"));
-    verifyNumOfRows(result, 0);
+    verifyNumOfRows(result, 5);
     resetSubsearchMaxOut();
   }
 }

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

@@ -311,7 +311,7 @@ public void testNestedScalarSubqueryWithTableAlias() throws IOException {
   }
 
   @Test
-  public void testSubsearchMaxOutZero() throws IOException {
+  public void testSubsearchMaxOutZeroMeansUnlimited() throws IOException {
     setSubsearchMaxOut(0);
     JSONObject result =
         executeQuery(
@@ -322,7 +322,7 @@ public void testSubsearchMaxOutZero() throws IOException {
                     + "  ]"
                     + "| fields id, name",
                 TEST_INDEX_WORKER, TEST_INDEX_WORK_INFORMATION));
-    verifyNumOfRows(result, 0);
+    verifyNumOfRows(result, 5);
     resetSubsearchMaxOut();
   }
 }

integ-test/src/test/java/org/opensearch/sql/calcite/standalone/MapConcatFunctionIT.java

@@ -26,6 +26,7 @@
 import org.apache.calcite.tools.RelBuilder;
 import org.junit.jupiter.api.Test;
 import org.opensearch.sql.calcite.CalcitePlanContext;
+import org.opensearch.sql.calcite.SysLimit;
 import org.opensearch.sql.calcite.utils.CalciteToolsHelper.OpenSearchRelRunners;
 import org.opensearch.sql.common.setting.Settings;
 import org.opensearch.sql.executor.QueryType;
@@ -175,6 +176,6 @@ private CalcitePlanContext createCalcitePlanContext() {
 
     Settings settings = getSettings();
     return CalcitePlanContext.create(
-        config.build(), settings.getSettingValue(Settings.Key.QUERY_SIZE_LIMIT), QueryType.PPL);
+        config.build(), SysLimit.fromSettings(settings), QueryType.PPL);
   }
 }

opensearch/src/main/java/org/opensearch/sql/opensearch/setting/OpenSearchSettings.java

@@ -133,15 +133,13 @@ public class OpenSearchSettings extends Settings {
       Setting.intSetting(
           Key.PPL_SUBSEARCH_MAXOUT.getKeyValue(),
           10000,
-          -1,
           Setting.Property.NodeScope,
           Setting.Property.Dynamic);
 
   public static final Setting<?> PPL_JOIN_SUBSEARCH_MAXOUT_SETTING =
       Setting.intSetting(
           Key.PPL_JOIN_SUBSEARCH_MAXOUT.getKeyValue(),
           50000,
-          -1,
           Setting.Property.NodeScope,
           Setting.Property.Dynamic);
 

ppl/src/test/java/org/opensearch/sql/ppl/calcite/CalcitePPLExistsSubqueryTest.java

@@ -725,7 +725,7 @@ public void testSubsearchMaxOutUncorrelated2() {
   }
 
   @Test
-  public void testSubsearchMaxOutZero() {
+  public void testSubsearchMaxOutZeroMeansUnlimited() {
     doReturn(0).when(settings).getSettingValue(Settings.Key.PPL_SUBSEARCH_MAXOUT);
     String ppl =
         """
@@ -742,7 +742,8 @@ public void testSubsearchMaxOutZero() {
             + "LogicalProject(EMPNO=[$0], ENAME=[$1])\n"
             + "  LogicalSort(sort0=[$0], dir0=[DESC-nulls-last])\n"
             + "    LogicalFilter(condition=[EXISTS({\n"
-            + "LogicalValues(tuples=[[]])\n"
+            + "LogicalFilter(condition=[AND(=($cor0.SAL, $2), >($1, 1000.0:DECIMAL(5, 1)))])\n"
+            + "  LogicalTableScan(table=[[scott, SALGRADE]])\n"
             + "})], variablesSet=[[$cor0]])\n"
             + "      LogicalTableScan(table=[[scott, EMP]])\n";
     verifyLogical(root, expectedLogical);
@@ -751,14 +752,14 @@ public void testSubsearchMaxOutZero() {
         "SELECT `EMPNO`, `ENAME`\n"
             + "FROM `scott`.`EMP`\n"
             + "WHERE EXISTS (SELECT *\n"
-            + "FROM (VALUES (NULL, NULL, NULL)) `t` (`GRADE`, `LOSAL`, `HISAL`)\n"
-            + "WHERE 1 = 0)\n"
+            + "FROM `scott`.`SALGRADE`\n"
+            + "WHERE `EMP`.`SAL` = `HISAL` AND `LOSAL` > 1000.0)\n"
             + "ORDER BY `EMPNO` DESC";
     verifyPPLToSparkSQL(root, expectedSparkSql);
   }
 
   @Test
-  public void testSubsearchMaxOutUnlimited() {
+  public void testSubsearchMaxOutNegativeMeansUnlimited() {
     doReturn(-1).when(settings).getSettingValue(Settings.Key.PPL_SUBSEARCH_MAXOUT);
     String ppl =
         """
@@ -780,14 +781,5 @@ public void testSubsearchMaxOutUnlimited() {
             + "})], variablesSet=[[$cor0]])\n"
             + "      LogicalTableScan(table=[[scott, EMP]])\n";
     verifyLogical(root, expectedLogical);
-
-    String expectedSparkSql =
-        "SELECT `EMPNO`, `ENAME`\n"
-            + "FROM `scott`.`EMP`\n"
-            + "WHERE EXISTS (SELECT *\n"
-            + "FROM `scott`.`SALGRADE`\n"
-            + "WHERE `EMP`.`SAL` = `HISAL` AND `LOSAL` > 1000.0)\n"
-            + "ORDER BY `EMPNO` DESC";
-    verifyPPLToSparkSQL(root, expectedSparkSql);
   }
 }