#1057, #1072 fix subquery result cache in lazy mode

h2/src/main/org/h2/command/dml/Query.java

@@ -397,7 +397,7 @@ public abstract class Query extends Prepared {
         }
         fireBeforeSelectTriggers();
         if (noCache || !session.getDatabase().getOptimizeReuseResults() ||
-                session.isLazyQueryExecution()) {
+                (session.isLazyQueryExecution() && !neverLazy)) {
             return queryWithoutCacheLazyCheck(limit, target);
         }
         Value[] params = getParameterValues();

h2/src/main/org/h2/index/ViewIndex.java

@@ -285,6 +285,7 @@ public class ViewIndex extends BaseIndex implements SpatialIndex {
             return findRecursive(first, last);
         }
         setupQueryParameters(session, first, last, intersection);
+        query.setNeverLazy(true);
         ResultInterface result = query.query(0);
         return new ViewCursor(this, result, first, last);
     }

h2/src/test/org/h2/test/TestAll.java

@@ -167,68 +167,7 @@ import org.h2.test.synth.TestStringAggCompatibility;
 import org.h2.test.synth.TestTimer;
 import org.h2.test.synth.sql.TestSynth;
 import org.h2.test.synth.thread.TestMulti;
-import org.h2.test.unit.TestAnsCompression;
-import org.h2.test.unit.TestAutoReconnect;
-import org.h2.test.unit.TestBinaryArithmeticStream;
-import org.h2.test.unit.TestBitStream;
-import org.h2.test.unit.TestBnf;
-import org.h2.test.unit.TestCache;
-import org.h2.test.unit.TestCharsetCollator;
-import org.h2.test.unit.TestClearReferences;
-import org.h2.test.unit.TestCollation;
-import org.h2.test.unit.TestCompress;
-import org.h2.test.unit.TestConnectionInfo;
-import org.h2.test.unit.TestDataPage;
-import org.h2.test.unit.TestDate;
-import org.h2.test.unit.TestDateIso8601;
-import org.h2.test.unit.TestDateTimeUtils;
-import org.h2.test.unit.TestDbException;
-import org.h2.test.unit.TestExit;
-import org.h2.test.unit.TestFile;
-import org.h2.test.unit.TestFileLock;
-import org.h2.test.unit.TestFileLockProcess;
-import org.h2.test.unit.TestFileLockSerialized;
-import org.h2.test.unit.TestFileSystem;
-import org.h2.test.unit.TestFtp;
-import org.h2.test.unit.TestGeometryUtils;
-import org.h2.test.unit.TestIntArray;
-import org.h2.test.unit.TestIntIntHashMap;
-import org.h2.test.unit.TestIntPerfectHash;
-import org.h2.test.unit.TestInterval;
-import org.h2.test.unit.TestJmx;
-import org.h2.test.unit.TestLocalResultFactory;
-import org.h2.test.unit.TestLocale;
-import org.h2.test.unit.TestMathUtils;
-import org.h2.test.unit.TestMemoryUnmapper;
-import org.h2.test.unit.TestMode;
-import org.h2.test.unit.TestModifyOnWrite;
-import org.h2.test.unit.TestNetUtils;
-import org.h2.test.unit.TestObjectDeserialization;
-import org.h2.test.unit.TestOldVersion;
-import org.h2.test.unit.TestOverflow;
-import org.h2.test.unit.TestPageStore;
-import org.h2.test.unit.TestPageStoreCoverage;
-import org.h2.test.unit.TestPattern;
-import org.h2.test.unit.TestPerfectHash;
-import org.h2.test.unit.TestPgServer;
-import org.h2.test.unit.TestReader;
-import org.h2.test.unit.TestRecovery;
-import org.h2.test.unit.TestReopen;
-import org.h2.test.unit.TestSampleApps;
-import org.h2.test.unit.TestScriptReader;
-import org.h2.test.unit.TestSecurity;
-import org.h2.test.unit.TestShell;
-import org.h2.test.unit.TestSort;
-import org.h2.test.unit.TestStreams;
-import org.h2.test.unit.TestStringCache;
-import org.h2.test.unit.TestStringUtils;
-import org.h2.test.unit.TestTimeStampWithTimeZone;
-import org.h2.test.unit.TestTools;
-import org.h2.test.unit.TestTraceSystem;
-import org.h2.test.unit.TestUtils;
-import org.h2.test.unit.TestValue;
-import org.h2.test.unit.TestValueHashMap;
-import org.h2.test.unit.TestValueMemory;
+import org.h2.test.unit.*;
 import org.h2.test.utils.OutputCatcher;
 import org.h2.test.utils.SelfDestructor;
 import org.h2.test.utils.TestColumnNamer;
@@ -988,6 +927,7 @@ kill -9 `jps -l | grep "org.h2.test." | cut -d " " -f 1`
         addTest(new TestUtils());
         addTest(new TestValueHashMap());
         addTest(new TestLocalResultFactory());
+        addTest(new TestSubqueryPerformanceOnLazyExecutionMode());
 
         runAddedTests();
 

h2/src/test/org/h2/test/unit/TestSubqueryPerformanceOnLazyExecutionMode.java

+/*
+ * Copyright 2004-2018 H2 Group. Multiple-Licensed under the MPL 2.0,
+ * and the EPL 1.0 (http://h2database.com/html/license.html).
+ * Initial Developer: H2 Group
+ */
+package org.h2.test.unit;
+
+import org.h2.command.dml.SetTypes;
+import org.h2.test.TestBase;
+import org.junit.Assert;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.sql.Statement;
+
+/**
+ * Test subquery performance with lazy query execution mode {@link SetTypes#LAZY_QUERY_EXECUTION}.
+ */
+public class TestSubqueryPerformanceOnLazyExecutionMode extends TestBase {
+    /** Rows count. */
+    private static final int ROWS = 5000;
+
+    /**
+     * Run just this test.
+     *
+     * @param a ignored
+     */
+    public static void main(String[] a) throws Exception {
+        TestBase.createCaller().init().test();
+    }
+
+
+    @Override
+    public void test() throws Exception {
+        Class.forName("org.h2.Driver");
+        try (Connection conn = DriverManager.getConnection("jdbc:h2:mem:")) {
+            try (Statement stmt = conn.createStatement()) {
+                stmt.execute("CREATE TABLE ONE(X INTEGER , Y INTEGER )");
+
+                try (PreparedStatement prep = conn.prepareStatement("insert into one values(?,?)")) {
+                    for (int row = 0; row < ROWS; row++) {
+                        prep.setInt(1, row / 100);
+                        prep.setInt(2, row);
+                        prep.execute();
+                    }
+                }
+
+                testSubqueryInCondition(stmt);
+                testSubqueryInJoin(stmt);
+            }
+        }
+    }
+
+    public void testSubqueryInCondition(Statement stmt) throws Exception {
+        String sql = "SELECT COUNT (*) FROM one WHERE x IN (SELECT y FROM one WHERE y < 50)";
+
+        long tNotLazy = executeAndCheckResult(stmt, sql, false);
+        long tLazy = executeAndCheckResult(stmt, sql, true);
+
+        Assert.assertTrue("Lazy execution too slow. lazy time: "
+                        + tLazy + ", not lazy time: " + tNotLazy,
+                tNotLazy * 2 > tLazy);
+    }
+
+    public void testSubqueryInJoin(Statement stmt) throws Exception {
+        String sql =
+                "SELECT COUNT (one.x) FROM one " +
+                "JOIN (SELECT y AS val FROM one WHERE y < 50) AS subq ON subq.val=one.x";
+
+        long tNotLazy = executeAndCheckResult(stmt, sql, false);
+        long tLazy = executeAndCheckResult(stmt, sql, true);
+
+        Assert.assertTrue("Lazy execution too slow. lazy time: "
+                        + tLazy + ", not lazy time: " + tNotLazy,
+                tNotLazy * 2 > tLazy);
+    }
+
+    /**
+     * @return Time of the query execution.
+     */
+    private long executeAndCheckResult(Statement stmt, String sql, boolean lazy) throws SQLException {
+        if (lazy) {
+            stmt.execute("SET LAZY_QUERY_EXECUTION 1");
+        }
+        else {
+            stmt.execute("SET LAZY_QUERY_EXECUTION 0");
+        }
+
+        long t0 = System.currentTimeMillis();
+        try (ResultSet rs = stmt.executeQuery(sql)) {
+            rs.next();
+            Assert.assertEquals(ROWS, rs.getInt(1));
+        }
+
+        return System.currentTimeMillis() - t0;
+    }
+}