Added support of concurrent_result_sets option

query/src/main/java/tech/ydb/query/impl/SessionImpl.java

@@ -182,31 +182,26 @@ private static YdbQuery.StatsMode mapStatsMode(QueryStatsMode mode) {
         }
     }
 
-    private String mapPoolId(ExecuteQuerySettings settings) {
-        String actualPoolId = settings.getResourcePool();
-
-        if (actualPoolId == null) {
-            return YdbQuery.ExecuteQueryRequest.getDefaultInstance().getPoolId();
-        }
-
-        return actualPoolId;
-    }
-
     GrpcReadStream<YdbQuery.ExecuteQueryResponsePart> createGrpcStream(
             String query, YdbQuery.TransactionControl tx, Params prms, ExecuteQuerySettings settings
     ) {
         YdbQuery.ExecuteQueryRequest.Builder requestBuilder = YdbQuery.ExecuteQueryRequest.newBuilder()
                 .setSessionId(sessionId)
                 .setExecMode(mapExecMode(settings.getExecMode()))
                 .setStatsMode(mapStatsMode(settings.getStatsMode()))
+                .setConcurrentResultSets(settings.isConcurrentResultSets())
                 .setQueryContent(YdbQuery.QueryContent.newBuilder()
                         .setSyntax(YdbQuery.Syntax.SYNTAX_YQL_V1)
                         .setText(query)
                         .build()
                 )
-                .setPoolId(mapPoolId(settings))
                 .putAllParameters(prms.toPb());
 
+        String resourcePool = settings.getResourcePool();
+        if (resourcePool != null && !resourcePool.isEmpty()) {
+            requestBuilder.setPoolId(resourcePool);
+        }
+
         if (tx != null) {
             requestBuilder.setTxControl(tx);
         }

query/src/main/java/tech/ydb/query/settings/ExecuteQuerySettings.java

@@ -9,16 +9,14 @@
 public class ExecuteQuerySettings extends BaseRequestSettings {
     private final QueryExecMode execMode;
     private final QueryStatsMode statsMode;
-
-    /**
-     * Resource pool
-     */
+    private final boolean concurrentResultSets;
     private final String resourcePool;
 
     private ExecuteQuerySettings(Builder builder) {
         super(builder);
         this.execMode = builder.execMode;
         this.statsMode = builder.statsMode;
+        this.concurrentResultSets = builder.concurrentResultSets;
         this.resourcePool = builder.resourcePool;
     }
 
@@ -30,6 +28,14 @@ public QueryStatsMode getStatsMode() {
         return this.statsMode;
     }
 
+    public boolean isConcurrentResultSets() {
+        return this.concurrentResultSets;
+    }
+
+    /**
+     * Get resource pool for query execution
+     * @return resource pool name
+     */
     public String getResourcePool() {
         return this.resourcePool;
     }
@@ -41,6 +47,7 @@ public static Builder newBuilder() {
     public static class Builder extends BaseBuilder<Builder> {
         private QueryExecMode execMode = QueryExecMode.EXECUTE;
         private QueryStatsMode statsMode = QueryStatsMode.NONE;
+        private boolean concurrentResultSets = false;
         private String resourcePool = null;
 
         public Builder withExecMode(QueryExecMode mode) {
@@ -53,12 +60,17 @@ public Builder withStatsMode(QueryStatsMode mode) {
             return this;
         }
 
+        public Builder withConcurrentResultSets(boolean value) {
+            this.concurrentResultSets = value;
+            return this;
+        }
+
         /**
          * Set resource pool which query try to use.
          * If no pool specify or poolId is empty or poolId equals "default"
-         * the undeleted resource pool "default" wll be used
+         * the unremovable resource pool "default" will be used
          *
-         * @param poolId poolId in ydb
+         * @param poolId resource pool identifier
          *
          * @return builder
          */

query/src/test/java/tech/ydb/query/impl/QueryIntegrationTest.java

@@ -1,9 +1,13 @@
 package tech.ydb.query.impl;
 
 import java.time.Duration;
+import java.util.ArrayDeque;
 import java.util.ArrayList;
+import java.util.Deque;
+import java.util.HashSet;
 import java.util.Iterator;
 import java.util.List;
+import java.util.Set;
 import java.util.concurrent.CompletableFuture;
 
 import org.junit.AfterClass;
@@ -315,6 +319,46 @@ public void updateMultipleTablesInOneTransaction() {
         }
     }
 
+    @Test
+    public void concurrentResultSetsTest() {
+        try (QueryClient client = QueryClient.newClient(ydbTransport).build()) {
+            try (QuerySession session = client.createSession(Duration.ofSeconds(5)).join().getValue()) {
+                String query = ""
+                        + "SELECT id, name, payload, is_valid FROM " + TEST_TABLE + " ORDER BY id;\n"
+                        + "SELECT 3 + 5;\n"
+                        + "SELECT id, name, payload, is_valid FROM " + TEST_TABLE + " ORDER BY id DESC;\n"
+                        + "SELECT 3 + 1;\n";
+
+                // consistent read - all result sets are ordered
+                QueryStream qs1 = session.createQuery(query, TxMode.SNAPSHOT_RO, Params.empty(),
+                        ExecuteQuerySettings.newBuilder().withConcurrentResultSets(false).build());
+
+                Deque<Long> ordered = new ArrayDeque<>();
+                Result<QueryInfo> res1 = qs1.execute(part -> {
+                    Long id = part.getResultSetIndex();
+                    if (!ordered.isEmpty()) {
+                        Assert.assertTrue(id >= ordered.getLast());
+                    }
+                    ordered.addLast(id);
+                }).join();
+                Assert.assertTrue(res1.isSuccess());
+
+                // concurrent read - all result sets are unordered
+                QueryStream qs2 = session.createQuery(query, TxMode.SNAPSHOT_RO, Params.empty(),
+                        ExecuteQuerySettings.newBuilder().withConcurrentResultSets(true).build());
+
+                Set<Long> unordered = new HashSet<>();
+                Result<QueryInfo> res2 = qs2.execute(part -> {
+                    unordered.add(part.getResultSetIndex());
+                }).join();
+                Assert.assertTrue(res2.isSuccess());
+
+                Assert.assertTrue(ordered.containsAll(unordered));
+                Assert.assertTrue(unordered.containsAll(ordered));
+            }
+        }
+    }
+
     @Test
     public void interactiveTransaction() {
         try (QueryClient client = QueryClient.newClient(ydbTransport).build()) {