Issue 101: Rollback of a large transaction could fail.

h2/src/docsrc/html/changelog.html

@@ -18,7 +18,8 @@ Change Log
 <h1>Change Log</h1>
 
 <h2>Next Version (unreleased)</h2>
-<ul><li>Various improvements in the page store mechanism (still experimental).
+<ul><li>Issue 101: Rollback of a large transaction could fail.
+</li><li>Various improvements in the page store mechanism (still experimental).
 </li><li>The functions LENGTH, OCTET_LENGTH, and BIT_LENGTH now return BIGINT.
 </li><li>Data types CLOB and BLOB: the maximum precision was Integer.MAX_VALUE, it is now Long.MAX_VALUE.
 </li><li>Multi-threaded kernel: creating and dropping temporary database objects

h2/src/main/org/h2/log/UndoLog.java

@@ -85,6 +85,10 @@ public class UndoLog {
                     }
                 }
             }
+            for (int k = 0; k < i; k++) {
+                UndoLogRecord e = records.get(k);
+                e.invalidatePos();
+            }
             first.seek(file);
         }
         return entry;

h2/src/main/org/h2/log/UndoLogRecord.java

@@ -100,6 +100,7 @@ public class UndoLogRecord {
                 }
             }
             try {
+                row.setDeleted(false);
                 table.removeRow(session, row);
             } catch (SQLException e) {
                 if (session.getDatabase().getLockMode() == Constants.LOCK_MODE_OFF
@@ -117,6 +118,7 @@ public class UndoLogRecord {
                 table.addRow(session, row);
                 // reset session id, otherwise other session think
                 // that this row was inserted by this session
+                commit();
                 row.commit();
             } catch (SQLException e) {
                 if (session.getDatabase().getLockMode() == Constants.LOCK_MODE_OFF
@@ -133,6 +135,15 @@ public class UndoLogRecord {
         }
     }
 
+    /**
+     * Go to the right position in the file.
+     *
+     * @param file the file
+     */
+    void seek(FileStore file) throws SQLException {
+        file.seek(filePos * Constants.FILE_BLOCK_SIZE);
+    }
+
     /**
      * Save the row in the file using the data page as a buffer.
      *
@@ -143,6 +154,8 @@ public class UndoLogRecord {
         buff.reset();
         buff.writeInt(0);
         buff.writeInt(operation);
+        buff.writeByte(row.isDeleted() ? (byte) 1 : (byte) 0);
+        buff.writeInt(row.getSessionId());
         buff.writeInt(row.getColumnCount());
         for (int i = 0; i < row.getColumnCount(); i++) {
             buff.writeValue(row.getValue(i));
@@ -156,15 +169,6 @@ public class UndoLogRecord {
         state = STORED;
     }
 
-    /**
-     * Go to the right position in the file.
-     *
-     * @param file the file
-     */
-    void seek(FileStore file) throws SQLException {
-        file.seek(filePos * Constants.FILE_BLOCK_SIZE);
-    }
-
     /**
      * Load an undo log record row using the data page as a buffer.
      *
@@ -188,12 +192,16 @@ public class UndoLogRecord {
                 Message.throwInternalError("operation=" + operation + " op=" + op);
             }
         }
+        boolean deleted = buff.readByte() == 1;
+        int sessionId = buff.readInt();
         int columnCount = buff.readInt();
         Value[] values = new Value[columnCount];
         for (int i = 0; i < columnCount; i++) {
             values[i] = buff.readValue();
         }
         row = new Row(values, 0);
+        row.setDeleted(deleted);
+        row.setSessionId(sessionId);
         state = IN_MEMORY_READ_POS;
     }
 
@@ -224,4 +232,15 @@ public class UndoLogRecord {
     public Row getRow() {
         return row;
     }
+
+    /**
+     * Change the state from IN_MEMORY to IN_MEMORY_READ_POS. This method is
+     * called if a later record was read from the temporary file, and therefore
+     * the position could have changed.
+     */
+    void invalidatePos() {
+        if (this.state == IN_MEMORY) {
+            state = IN_MEMORY_READ_POS;
+        }
+    }
 }

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

@@ -17,7 +17,6 @@ import java.sql.Statement;
 import java.sql.Time;
 import java.sql.Timestamp;
 import java.util.Random;
-
 import org.h2.constant.ErrorCode;
 import org.h2.test.TestBase;
 
@@ -36,6 +35,7 @@ public class TestCases extends TestBase {
     }
 
     public void test() throws Exception {
+        testLargeRollback();
         testConstraintAlterTable();
         testJoinWithView();
         testLobDecrypt();
@@ -72,6 +72,18 @@ public class TestCases extends TestBase {
         deleteDb("cases");
     }
 
+    private void testLargeRollback() throws SQLException {
+        deleteDb("cases");
+        Connection conn = getConnection("cases");
+        conn.createStatement().execute("set MAX_MEMORY_UNDO 8");
+        conn.createStatement().execute("create table test(id number primary key)");
+        conn.setAutoCommit(false);
+        conn.createStatement().execute("insert into test select x from system_range(1, 10)");
+        conn.createStatement().execute("delete from test");
+        conn.rollback();
+        conn.close();
+    }
+
     private void testConstraintAlterTable() throws SQLException {
         deleteDb("cases");
         Connection conn = getConnection("cases");