The database upgrade (to upgrade from H2 version 1.1.x) has been simplified.

h2/src/main/org/h2/Driver.java

@@ -6,6 +6,7 @@
  */
 package org.h2;
 
+import java.sql.Connection;
 import java.sql.DriverManager;
 import java.sql.DriverPropertyInfo;
 import java.sql.SQLException;
@@ -46,7 +47,7 @@ public class Driver implements java.sql.Driver {
      * @param info the connection properties
      * @return the new connection or null if the URL is not supported
      */
-    public JdbcConnection connect(String url, Properties info) throws SQLException {
+    public Connection connect(String url, Properties info) throws SQLException {
         try {
             if (info == null) {
                 info = new Properties();
@@ -54,7 +55,10 @@ public class Driver implements java.sql.Driver {
             if (!acceptsURL(url)) {
                 return null;
             }
-            DbUpgrade.upgradeIfRequired(url, info);
+            Connection c = DbUpgrade.connctOrUpgrade(url, info);
+            if (c != null) {
+                return c;
+            }
             return new JdbcConnection(url, info);
         } catch (Exception e) {
             throw DbException.toSQLException(e);

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

@@ -83,7 +83,7 @@ public class ConnectionInfo implements Cloneable {
         set.addAll(list);
         String[] connectionTime = { "ACCESS_MODE_DATA", "AUTOCOMMIT", "CIPHER",
                 "CREATE", "CACHE_TYPE", "FILE_LOCK", "IGNORE_UNKNOWN_SETTINGS", "IFEXISTS",
-                "INIT", "PASSWORD", "RECOVER", "USER", "AUTO_SERVER",
+                "INIT", "PASSWORD", "RECOVER", "USER", "AUTO_SERVER", "NO_UPGRADE",
                 "AUTO_RECONNECT", "OPEN_NEW", "PAGE_SIZE", "PASSWORD_HASH", "JMX" };
         for (String key : connectionTime) {
             if (SysProperties.CHECK && set.contains(key)) {

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

@@ -40,6 +40,7 @@ public class Engine implements SessionFactory {
     private Session openSession(ConnectionInfo ci, boolean ifExists, String cipher) {
         String name = ci.getName();
         Database database;
+        ci.removeProperty("NO_UPGRADE", false);
         boolean openNew = ci.getProperty("OPEN_NEW", false);
         if (openNew || ci.isUnnamedInMemory()) {
             database = null;

h2/src/main/org/h2/jdbcx/JdbcDataSource.java

@@ -177,11 +177,13 @@ implements XADataSource, DataSource, ConnectionPoolDataSource, Serializable, Ref
         Properties info = new Properties();
         info.setProperty("user", user);
         info.put("password", password);
-        JdbcConnection conn = Driver.load().connect(url, info);
+        Connection conn = Driver.load().connect(url, info);
         if (conn == null) {
             throw new SQLException("No suitable driver found for " + url, "08001", 8001);
+        } else if (!(conn instanceof JdbcConnection)) {
+            throw new SQLException("Connecting with old version is not supported: " + url, "08001", 8001);
         }
-        return conn;
+        return (JdbcConnection) conn;
     }
 
     /**

h2/src/main/org/h2/upgrade/DbUpgrade.java

@@ -45,9 +45,9 @@ public class DbUpgrade {
      * @param url the database URL
      * @param info the properties
      */
-    public static void upgradeIfRequired(String url, Properties info) throws SQLException {
+    public static Connection connctOrUpgrade(String url, Properties info) throws SQLException {
         if (!upgradeClassesPresent) {
-            return;
+            return null;
         }
         Properties i2 = new Properties();
         i2.putAll(info);
@@ -59,18 +59,21 @@ public class DbUpgrade {
         info = i2;
         ConnectionInfo ci = new ConnectionInfo(url, info);
         if (ci.isRemote() || !ci.isPersistent()) {
-            return;
+            return null;
         }
         String name = ci.getName();
         if (Database.exists(name)) {
-            return;
+            return null;
         }
         if (!IOUtils.exists(name + ".data.db")) {
-            return;
+            return null;
+        }
+        if (ci.removeProperty("NO_UPGRADE", false)) {
+            return connectWithOldVersion(url, info);
         }
         synchronized (DbUpgrade.class) {
             upgrade(ci, info);
-            return;
+            return null;
         }
     }
 
@@ -97,6 +100,11 @@ public class DbUpgrade {
         DbUpgrade.deleteOldDb = deleteOldDb;
     }
 
+    private static Connection connectWithOldVersion(String url, Properties info) throws SQLException {
+        url = "jdbc:h2v1_1:" + url.substring("jdbc:h2:".length()) + ";IGNORE_UNKNOWN_SETTINGS=TRUE";
+        return DriverManager.getConnection(url, info);
+    }
+
     private static void upgrade(ConnectionInfo ci, Properties info) throws SQLException {
         String name = ci.getName();
         String data = name + ".data.db";

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

@@ -93,10 +93,7 @@ public class TestUpgrade extends TestBase {
         assertTrue(IOUtils.exists(getBaseDir() + "/upgrade.h2.db"));
         deleteDb("upgrade");
 
-        conn = getConnection("jdbc:h2v1_1:" + getBaseDir() + "/upgrade");
-        conn.close();
-
-        conn = getConnection("upgrade");
+        conn = getConnection("upgrade;NO_UPGRADE=TRUE");
         conn.close();
         assertTrue(IOUtils.exists(getBaseDir() + "/upgrade.h2.db"));
         deleteDb("upgrade");