/** Initialize the scan, returning false if there was some error. */
  public boolean init(TransactionManager tran) throws StandardException {
    if (SanityManager.DEBUG) {
      // We really expect to have at least one
      // merge run.
      SanityManager.ASSERT(mergeRuns != null);
      SanityManager.ASSERT(mergeRuns.size() > 0);

      // This sort scan also expects that the
      // caller has ensured that the sort buffer
      // capacity will hold a row from all the
      // merge runs.
      SanityManager.ASSERT(sortBuffer.capacity() >= mergeRuns.size());
    }

    // Clear the sort buffer.
    sortBuffer.reset();

    // Create an array to hold a scan controller
    // for each merge run.
    openScans = new StreamContainerHandle[mergeRuns.size()];
    if (openScans == null) return false;

    // Open a scan on each merge run.
    int scanindex = 0;
    Enumeration e = mergeRuns.elements();
    while (e.hasMoreElements()) {
      // get the container id
      long id = ((Long) e.nextElement()).longValue();

      Transaction rawTran = tran.getRawStoreXact(); // get raw transaction
      int segmentId = StreamContainerHandle.TEMPORARY_SEGMENT;
      openScans[scanindex++] = rawTran.openStreamContainer(segmentId, id, hold);
    }

    // Load the initial rows.
    for (scanindex = 0; scanindex < openScans.length; scanindex++) mergeARow(scanindex);

    // Success!
    return true;
  }
Example #2
0
  /**
   * Create an empty secondary index b-tree, using the generic b-tree to do the generic part of the
   * creation process.
   *
   * <p>This routine opens the newly created container, adds a single page, and makes this page the
   * root by inserting a LeafControlRow onto this page at slot 0 and marking in that control row
   * that the page is a root page.
   *
   * <p>The following properties are specific to the b-tree secondary index:
   *
   * <UL>
   *   <LI>"baseConglomerateId" (integer). The conglomerate id of the base conglomerate is never
   *       actually accessed by the b-tree secondary index implementation, it only serves as a
   *       namespace for row locks. This property is required.
   *   <LI>"rowLocationColumn" (integer). The zero-based index into the row which the b-tree
   *       secondary index will assume holds a @see RowLocation of the base row in the base
   *       conglomerate. This value will be used for acquiring locks. In this implementation
   *       RowLocationColumn must be the last key column. This property is required.
   * </UL>
   *
   * A secondary index i (a, b) on table t (a, b, c) would have rows which looked like (a, b,
   * row_location). baseConglomerateId is set to the conglomerate id of t. rowLocationColumns is set
   * to 2. allowsDuplicates would be set to false, @see BTree#create. To create a unique secondary
   * index set uniquenessColumns to 2, this means that the btree code will compare the key values
   * but not the row id when determing uniqueness. To create a nonunique secondary index set
   * uniquenessColumns to 3, this would mean that the uniqueness test would include the row location
   * and since all row locations will be unique all rows inserted into the index will be
   * differentiated (at least) by row location.
   *
   * @see BTree#create
   * @exception StandardException Standard exception policy.
   */
  public void create(
      TransactionManager xact_manager,
      int segmentId,
      long input_conglomid,
      DataValueDescriptor[] template,
      ColumnOrdering[] columnOrder,
      int[] collationIds,
      Properties properties,
      int temporaryFlag)
      throws StandardException {
    String property_value = null;
    Transaction rawtran = xact_manager.getRawStoreXact();

    if (properties == null) {
      throw (StandardException.newException(
          SQLState.BTREE_PROPERTY_NOT_FOUND, PROPERTY_BASECONGLOMID));
    }

    // Get baseConglomerateId //
    property_value = properties.getProperty(PROPERTY_BASECONGLOMID);
    if (property_value == null) {
      throw (StandardException.newException(
          SQLState.BTREE_PROPERTY_NOT_FOUND, PROPERTY_BASECONGLOMID));
    }

    if (SanityManager.DEBUG) {
      if (property_value == null)
        SanityManager.THROWASSERT(PROPERTY_BASECONGLOMID + "property not passed to B2I.create()");
    }

    baseConglomerateId = Long.parseLong(property_value);

    // Get rowLocationColumn //
    property_value = properties.getProperty(PROPERTY_ROWLOCCOLUMN);

    if (SanityManager.DEBUG) {
      if (property_value == null)
        SanityManager.THROWASSERT(PROPERTY_ROWLOCCOLUMN + "property not passed to B2I.create()");
    }

    if (property_value == null) {
      throw (StandardException.newException(
          SQLState.BTREE_PROPERTY_NOT_FOUND, PROPERTY_BASECONGLOMID));
    }

    rowLocationColumn = Integer.parseInt(property_value);

    // Currently the row location column must be the last column (makes)
    // comparing the columns in the index easier.
    if (SanityManager.DEBUG) {
      SanityManager.ASSERT(
          rowLocationColumn == template.length - 1,
          "rowLocationColumn is not the last column in the index");
      SanityManager.ASSERT(template[rowLocationColumn] instanceof RowLocation);

      // There must be at least one key column
      if (rowLocationColumn < 1)
        SanityManager.THROWASSERT(
            "rowLocationColumn (" + rowLocationColumn + ") expected to be >= 1");
    }

    /* convert the sorting order information into a boolean array map.
     * If the sorting order for the columns is not provided, we
     * assign the default as Ascending Order.
     * array length is equal to template length, because column order
     * length changes whether it is unique or is non unique. store assumes
     * template length arrays. So, we make template length array and make
     * the last column as ascending instead of having lot of execeptions
     * code.
     */

    ascDescInfo = new boolean[template.length];
    for (int i = 0; i < ascDescInfo.length; i++) {
      if (columnOrder != null && i < columnOrder.length)
        ascDescInfo[i] = columnOrder[i].getIsAscending();
      else ascDescInfo[i] = true; // default values - ascending order
    }

    // get collation ids from input collation ids, store it in the
    // conglom state.
    collation_ids = ConglomerateUtil.createCollationIds(template.length, collationIds);
    hasCollatedTypes = hasCollatedColumns(collation_ids);

    // Do the generic part of creating the b-tree.
    super.create(
        rawtran,
        segmentId,
        input_conglomid,
        template,
        properties,
        getTypeFormatId(),
        temporaryFlag);

    // open the base conglomerate - to get the lock
    ConglomerateController base_cc =
        xact_manager.openConglomerate(
            baseConglomerateId,
            false,
            TransactionController.OPENMODE_FOR_LOCK_ONLY,
            TransactionController.MODE_TABLE,
            TransactionController.ISOLATION_SERIALIZABLE);

    OpenBTree open_btree = new OpenBTree();

    BTreeLockingPolicy b2i_locking_policy =
        new B2ITableLocking3(
            rawtran,
            TransactionController.MODE_TABLE,
            rawtran.newLockingPolicy(
                LockingPolicy.MODE_CONTAINER, TransactionController.ISOLATION_SERIALIZABLE, true),
            base_cc,
            open_btree);

    // The following call will "open" the new btree.  Create is
    // an interesting case.  What we really want is read only table lock
    // on the base conglomerate and update locks on the index.  For now
    // just get the update lock on the base table, this is done by the
    // lockTable() call made by base class.

    open_btree.init(
        (TransactionManager) xact_manager, // current user xact
        (TransactionManager) xact_manager, // current xact
        (ContainerHandle) null, // have init open the container.
        rawtran,
        false,
        (ContainerHandle.MODE_FORUPDATE),
        TransactionController.MODE_TABLE,
        b2i_locking_policy, // get table level lock.
        this,
        (LogicalUndo) null, // no logical undo necessary, as
        // initEmptyBtree()
        // work will be done single user and
        // rows will not move.
        (DynamicCompiledOpenConglomInfo) null);

    // Open the newly created container, and insert the first control row.
    LeafControlRow.initEmptyBtree(open_btree);

    open_btree.close();

    base_cc.close();
  }
Example #3
0
  /**
   * Create a new btree locking policy from scratch.
   *
   * @exception StandardException Standard exception policy.
   */
  protected BTreeLockingPolicy getBtreeLockingPolicy(
      Transaction rawtran,
      int lock_level,
      int mode,
      int isolation_level,
      ConglomerateController base_cc,
      OpenBTree open_btree)
      throws StandardException {
    BTreeLockingPolicy ret_locking_policy = null;

    if (SanityManager.DEBUG) {
      SanityManager.ASSERT(
          (isolation_level == TransactionController.ISOLATION_SERIALIZABLE)
              || (isolation_level == TransactionController.ISOLATION_REPEATABLE_READ)
              || (isolation_level == TransactionController.ISOLATION_READ_COMMITTED_NOHOLDLOCK)
              || (isolation_level == TransactionController.ISOLATION_READ_COMMITTED)
              || (isolation_level == TransactionController.ISOLATION_READ_UNCOMMITTED),
          "bad isolation_level = " + isolation_level);
    }

    if (lock_level == TransactionController.MODE_TABLE) {
      ret_locking_policy =
          new B2ITableLocking3(
              rawtran,
              lock_level,
              rawtran.newLockingPolicy(LockingPolicy.MODE_CONTAINER, isolation_level, true),
              base_cc,
              open_btree);
    } else if (lock_level == TransactionController.MODE_RECORD) {
      if (isolation_level == TransactionController.ISOLATION_SERIALIZABLE) {
        ret_locking_policy =
            new B2IRowLocking3(
                rawtran,
                lock_level,
                rawtran.newLockingPolicy(LockingPolicy.MODE_RECORD, isolation_level, true),
                base_cc,
                open_btree);
      } else if ((isolation_level == TransactionController.ISOLATION_REPEATABLE_READ)) {
        ret_locking_policy =
            new B2IRowLockingRR(
                rawtran,
                lock_level,
                rawtran.newLockingPolicy(LockingPolicy.MODE_RECORD, isolation_level, true),
                base_cc,
                open_btree);
      } else if ((isolation_level == TransactionController.ISOLATION_READ_COMMITTED)
          || (isolation_level == TransactionController.ISOLATION_READ_COMMITTED_NOHOLDLOCK)) {
        ret_locking_policy =
            new B2IRowLocking2(
                rawtran,
                lock_level,
                rawtran.newLockingPolicy(LockingPolicy.MODE_RECORD, isolation_level, true),
                base_cc,
                open_btree);
      } else if (isolation_level == TransactionController.ISOLATION_READ_UNCOMMITTED) {
        ret_locking_policy =
            new B2IRowLocking1(
                rawtran,
                lock_level,
                rawtran.newLockingPolicy(LockingPolicy.MODE_RECORD, isolation_level, true),
                base_cc,
                open_btree);
      }
    }

    if (SanityManager.DEBUG) {
      SanityManager.ASSERT(ret_locking_policy != null, "ret_locking_policy == null");
    }

    return (ret_locking_policy);
  }