New sample application.

h2/src/test/org/h2/samples/RowAccessRights.java

+/*
+ * Copyright 2004-2011 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.samples;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.sql.Statement;
+import org.h2.tools.DeleteDbFiles;
+import org.h2.tools.TriggerAdapter;
+
+/**
+ * This sample application show how to emulate per-row access rights so that
+ * each user can only access rows created by the given user.
+ */
+public class RowAccessRights extends TriggerAdapter {
+
+    private PreparedStatement prepDelete, prepInsert;
+
+    /**
+     * Called when ran from command line.
+     *
+     * @param args ignored
+     */
+    public static void main(String... args) throws Exception {
+        DeleteDbFiles.execute("~", "test", true);
+
+        Class.forName("org.h2.Driver");
+        Connection conn = DriverManager.getConnection("jdbc:h2:~/test");
+        Statement stat = conn.createStatement();
+
+        stat.execute("create table test_data(id int, user varchar, data varchar, primary key(id, user))");
+        stat.execute("create index on test_data(id, user)");
+
+        stat.execute("create view test as select id, data from test_data where user = user()");
+        stat.execute("create trigger t_test instead of " +
+                "insert, update, delete on test for each row " +
+                "call \"" + RowAccessRights.class.getName() + "\"");
+        stat.execute("create user a password 'a'");
+        stat.execute("create user b password 'b'");
+        stat.execute("grant all on test to a");
+        stat.execute("grant all on test to b");
+
+        ResultSet rs;
+
+        Connection connA = DriverManager.getConnection("jdbc:h2:~/test", "a", "a");
+        Statement statA = connA.createStatement();
+        statA.execute("insert into test values(1, 'Hello'), (2, 'World')");
+        statA.execute("update test set data = 'Hello!' where id = 1");
+        statA.execute("delete from test where id = 2");
+
+        Connection connB = DriverManager.getConnection("jdbc:h2:~/test", "b", "b");
+        Statement statB = connB.createStatement();
+        statB.execute("insert into test values(1, 'Hallo'), (2, 'Welt')");
+        statB.execute("update test set data = 'Hallo!' where id = 1");
+        statB.execute("delete from test where id = 2");
+
+        rs = statA.executeQuery("select * from test");
+        while (rs.next()) {
+            System.out.println("a: " + rs.getInt(1) + "/" + rs.getString(2));
+        }
+
+        rs = statB.executeQuery("select * from test");
+        while (rs.next()) {
+            System.out.println("b: " + rs.getInt(1) + "/" + rs.getString(2));
+        }
+
+        connA.close();
+        connB.close();
+
+        rs = stat.executeQuery("select * from test_data");
+        while (rs.next()) {
+            System.out.println(rs.getInt(1) + "/" + rs.getString(2) + "/" + rs.getString(3));
+        }
+        conn.close();
+
+    }
+
+    public void init(Connection conn, String schemaName, String triggerName,
+            String tableName, boolean before, int type) throws SQLException {
+        prepDelete = conn.prepareStatement("delete from test_data where id = ? and user = ?");
+        prepInsert = conn.prepareStatement("insert into test_data values(?, ?, ?)");
+        super.init(conn, schemaName, triggerName, tableName, before, type);
+    }
+
+    public void fire(Connection conn, ResultSet oldRow, ResultSet newRow) throws SQLException {
+        String user = conn.getMetaData().getUserName();
+        if (oldRow != null && oldRow.next()) {
+            prepDelete.setInt(1, oldRow.getInt(1));
+            prepDelete.setString(2, user);
+            int deleted = prepDelete.executeUpdate();
+            if (deleted == 0 && newRow != null) {
+                // update:
+                // if deleting failed, insert must fail as well
+                newRow = null;
+            }
+        }
+        if (newRow != null && newRow.next()) {
+            prepInsert.setInt(1, newRow.getInt(1));
+            prepInsert.setString(2, user);
+            prepInsert.setString(3, newRow.getString(2));
+            prepInsert.executeUpdate();
+        }
+    }
+
+}

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

@@ -87,6 +87,12 @@ public class TestSampleApps extends TestBase {
                 "create the zip file...\n" +
                 "open the database from the zip file...",
                 org.h2.samples.ReadOnlyDatabaseInZip.class);
+        testApp(
+                "a: 1/Hello!\n" +
+                "b: 1/Hallo!\n" +
+                "1/A/Hello!\n" +
+                "1/B/Hallo!",
+                org.h2.samples.RowAccessRights.class);
 
         // tools
         testApp("Allows changing the database file encryption password or algorithm*",