start to implement row level locks

h2/src/main/org/h2/command/Command.java

@@ -176,8 +176,10 @@ public abstract class Command implements CommandInterface {
             session.commit(false);
         } else if (session.getDatabase().getMultiThreaded()) {
             Database db = session.getDatabase();
-            if (db != null && db.getLockMode() == Constants.LOCK_MODE_READ_COMMITTED) {
-                session.unlockReadLocks();
+            if (db != null) {
+                if (db.getLockMode() == Constants.LOCK_MODE_READ_COMMITTED) {
+                    session.unlockReadLocks();
+                }
             }
         }
         if (trace.isInfoEnabled()) {

h2/src/main/org/h2/engine/Constants.java

@@ -334,6 +334,13 @@ public class Constants {
      */
     public static final int LOCK_MODE_READ_COMMITTED = 3;
     
+    /**
+     * The lock mode that means row level locks are used if possible.
+     * This lock mode is similar to read committed, but row level locks are
+     * used instead of table level locks.
+     */
+    public static final int LOCK_MODE_ROW = 4;
+    
     /**
      * The lock mode that means table level locking is used for reads and
      * writes.

h2/src/main/org/h2/engine/Database.java

@@ -1741,7 +1741,17 @@ public class Database implements DataHandler {
         return maxMemoryUndo;
     }
 
-    public void setLockMode(int lockMode) {
+    public void setLockMode(int lockMode) throws SQLException {
+        switch (lockMode) {
+        case Constants.LOCK_MODE_OFF:
+        case Constants.LOCK_MODE_READ_COMMITTED:
+        case Constants.LOCK_MODE_TABLE:
+        case Constants.LOCK_MODE_TABLE_GC:
+        case Constants.LOCK_MODE_ROW:
+            break;
+        default:
+            throw Message.getInvalidValueException("lock mode", "" + lockMode);
+        }
         this.lockMode = lockMode;
     }
 

h2/src/main/org/h2/jdbc/JdbcConnection.java

@@ -684,6 +684,7 @@ public class JdbcConnection extends TraceObject implements Connection {
                 transactionIsolationLevel = Connection.TRANSACTION_READ_UNCOMMITTED;
                 break;
             case Constants.LOCK_MODE_READ_COMMITTED:
+            case Constants.LOCK_MODE_ROW:
                 transactionIsolationLevel = Connection.TRANSACTION_READ_COMMITTED;
                 break;
             case Constants.LOCK_MODE_TABLE:

h2/src/main/org/h2/table/TableData.java

@@ -377,13 +377,17 @@ public class TableData extends Table implements RecordReader {
                 }
             } else {
                 if (lockExclusive == null) {
-                    if (lockMode == Constants.LOCK_MODE_READ_COMMITTED && !database.getMultiThreaded() && !database.isMultiVersion()) {
-                        // READ_COMMITTED read locks are acquired but they
-                        // are released immediately
-                        // when allowing only one thread, no read locks are
-                        // required
-                        return;
-                    } else if (!lockShared.contains(session)) {
+                    if (lockMode == Constants.LOCK_MODE_READ_COMMITTED || lockMode == Constants.LOCK_MODE_ROW) {
+                        if (!database.getMultiThreaded() && !database.isMultiVersion()) {
+                            // READ_COMMITTED read locks are acquired but they
+                            // are released immediately
+                            // when allowing only one thread, no read locks are
+                            // required
+                            // row level locks work like read committed
+                            return;
+                        }
+                    } 
+                    if (!lockShared.contains(session)) {
                         traceLock(session, exclusive, "ok");
                         session.addLock(this);
                         lockShared.add(session);

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

@@ -72,6 +72,7 @@ import org.h2.test.jdbcx.TestXASimple;
 import org.h2.test.mvcc.TestMvcc1;
 import org.h2.test.mvcc.TestMvcc2;
 import org.h2.test.mvcc.TestMvcc3;
+import org.h2.test.rowlock.TestRowLocks;
 import org.h2.test.server.TestNestedLoop;
 import org.h2.test.server.TestPgServer;
 import org.h2.test.server.TestWeb;
@@ -266,6 +267,8 @@ java org.h2.test.TestAll timer
 
 /*
 
+row level locking
+
 run the performance tests as part of the unit test
 
 switch to JDK 1.6 by default
@@ -611,10 +614,11 @@ Roadmap:
         new TestWeb().runTest(this);
         new TestPgServer().runTest(this);
 
-        // mvcc
+        // mvcc & row level locking
         new TestMvcc1().runTest(this);
         new TestMvcc2().runTest(this);
         new TestMvcc3().runTest(this);
+        new TestRowLocks().runTest(this);
 
         // synth
         new TestCrashAPI().runTest(this);

h2/src/test/org/h2/test/db/TestCases.java

@@ -74,7 +74,7 @@ public class TestCases extends TestBase {
                 sql = "delete from " + table;
             }
             stat.execute(sql);
-            stat.execute("script to 'test.sql'");
+            stat.execute("script to '" + baseDir + "/test.sql'");
         }
         conn.close();
     }

h2/src/test/org/h2/test/db/TestCsv.java

@@ -104,11 +104,11 @@ public class TestCsv extends TestBase {
             list.add(new String[]{a, b});
             prep.execute();
         }
-        stat.execute("CALL CSVWRITE('test.csv', 'SELECT * FROM test', 'UTF-8', '|', '#')");
+        stat.execute("CALL CSVWRITE('" + baseDir + "/test.csv', 'SELECT * FROM test', 'UTF-8', '|', '#')");
         Csv csv = Csv.getInstance();
         csv.setFieldSeparatorRead('|');
         csv.setFieldDelimiter('#');
-        ResultSet rs = csv.read("test.csv", null, "UTF-8");
+        ResultSet rs = csv.read(baseDir + "/test.csv", null, "UTF-8");
         for (int i = 0; i < len; i++) {
             assertTrue(rs.next());
             String[] pair = (String[]) list.get(i);

h2/src/test/org/h2/test/rowlock/TestRowLocks.java

+/*
+ * Copyright 2004-2008 H2 Group. Multiple-Licensed under the H2 License, 
+ * Version 1.0, and under the Eclipse Public License, Version 1.0
+ * (http://h2database.com/html/license.html).
+ * Initial Developer: H2 Group
+ */
+package org.h2.test.rowlock;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.ResultSet;
+import java.sql.Statement;
+
+import org.h2.test.TestBase;
+import org.h2.tools.DeleteDbFiles;
+
+/**
+ * Row level locking tests.
+ */
+public class TestRowLocks extends TestBase {
+
+    private Connection c1, c2;
+    private Statement s1;
+
+    public void test() throws Exception {
+        testSetMode();
+        testCases();
+    }
+
+    private void testSetMode() throws Exception {
+        DeleteDbFiles.execute(null, "test", true);
+        Class.forName("org.h2.Driver");
+        c1 = DriverManager.getConnection("jdbc:h2:test", "sa", "sa");
+        Statement stat = c1.createStatement();
+        stat.execute("SET LOCK_MODE 4");
+        ResultSet rs = stat.executeQuery("call lock_mode()");
+        rs.next();
+        assertEquals("4", rs.getString(1));
+        c1.close();
+    }
+
+    private void testCases() throws Exception {
+        deleteDb("rowLocks");
+        c1 = getConnection("rowLocks");
+        s1 = c1.createStatement();
+        s1.execute("SET LOCK_MODE 4");
+        c2 = getConnection("rowLocks");
+        // s2 = c2.createStatement();
+        
+        c1.setAutoCommit(false);
+        c2.setAutoCommit(false);
+        
+        c1.close();
+        c2.close();
+    }
+
+}

h2/src/test/org/h2/test/rowlock/package.html

+<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
+<!--
+Copyright 2004-2008 H2 Group. Multiple-Licensed under the H2 License, Version 1.0,,
+and under the Eclipse Public License, Version 1.0
+(http://h2database.com/html/license.html).
+Initial Developer: H2 Group
+-->
+<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en">
+<head><meta http-equiv="Content-Type" content="text/html;charset=utf-8" /><title>
+Javadoc package documentation
+</title></head><body style="font: 9pt/130% Tahoma, Arial, Helvetica, sans-serif; font-weight: normal;">
+
+Row level locking tests.
+
+</body></html>
\ No newline at end of file

h2/src/test/org/h2/test/test.in.txt

 --- special grammar and test cases ---------------------------------------------------------------------------------------------
+CREATE TABLE T(A NULL);
+> exception
+
+CREATE TABLE T(A INT);
+> ok
+
+ALTER TABLE T ALTER COLUMN A NULL;
+> exception
+
+DROP TABLE T;
+> ok
+
 CREATE ROLE TEST_A;
 > ok
 

h2/src/test/org/h2/test/testSimple.in.txt

+create table test (id varchar(36) as random_uuid() primary key);
+insert into test() values();
+delete from test where id = select id from test;
+drop table test;
+create table test (id varchar(36) as now() primary key);
+insert into test() values();
+delete from test where id = select id from test;
+drop table test;
 SELECT SOME(X>4) FROM SYSTEM_RANGE(1,6);
 > TRUE;
 SELECT EVERY(X>4) FROM SYSTEM_RANGE(1,6);