Examples with ColumnOrdering org.apache.derby.iapi.store.access.ColumnOrdering used on opensource projects

Example 1 with ColumnOrdering

use of org.apache.derby.iapi.store.access.ColumnOrdering in project derby by apache.

the class GroupByNode method generate.

/**
 * generate the sort result set operating over the source
 * result set.  Adds distinct aggregates to the sort if
 * necessary.
 *
 * @exception StandardException		Thrown on error
 */
@Override
void generate(ActivationClassBuilder acb, MethodBuilder mb) throws StandardException {
    FormatableArrayHolder orderingHolder;
    /* Get the next ResultSet#, so we can number this ResultSetNode, its
		 * ResultColumnList and ResultSet.
		 */
    assignResultSetNumber();
    // Get the final cost estimate from the child.
    setCostEstimate(childResult.getFinalCostEstimate());
    /*
		** Get the column ordering for the sort.  Note that
		** for a scalar aggegate we may not have any ordering
		** columns (if there are no distinct aggregates).
		** WARNING: if a distinct aggregate is passed to
		** SortResultSet it assumes that the last column
		** is the distinct one.  If this assumption changes
		** then SortResultSet will have to change.
		*/
    orderingHolder = acb.getColumnOrdering(groupingList);
    if (addDistinctAggregate) {
        orderingHolder = acb.addColumnToOrdering(orderingHolder, addDistinctAggregateColumnNum);
    }
    if (SanityManager.DEBUG) {
        if (SanityManager.DEBUG_ON("AggregateTrace")) {
            StringBuilder s = new StringBuilder();
            s.append("Group by column ordering is (");
            ColumnOrdering[] ordering = orderingHolder.getArray(ColumnOrdering[].class);
            for (int i = 0; i < ordering.length; i++) {
                s.append(ordering[i].getColumnId());
                s.append(" ");
            }
            s.append(")");
            SanityManager.DEBUG("AggregateTrace", s.toString());
        }
    }
    int orderingItem = acb.addItem(orderingHolder);
    /*
		** We have aggregates, so save the aggInfo
		** struct in the activation and store the number
		*/
    if (SanityManager.DEBUG) {
        SanityManager.ASSERT(aggInfo != null, "aggInfo not set up as expected");
    }
    int aggInfoItem = acb.addItem(aggInfo);
    acb.pushGetResultSetFactoryExpression(mb);
    // Generate the child ResultSet
    childResult.generate(acb, mb);
    mb.push(isInSortedOrder);
    mb.push(aggInfoItem);
    mb.push(orderingItem);
    mb.push(acb.addItem(getResultColumns().buildRowTemplate()));
    mb.push(getResultColumns().getTotalColumnSize());
    mb.push(getResultSetNumber());
    /* Generate a (Distinct)ScalarAggregateResultSet if scalar aggregates */
    if ((groupingList == null) || (groupingList.size() == 0)) {
        genScalarAggregateResultSet(acb, mb);
    } else /* Generate a (Distinct)GroupedAggregateResultSet if grouped aggregates */
    {
        genGroupedAggregateResultSet(acb, mb);
    }
}

Example 2 with ColumnOrdering

use of org.apache.derby.iapi.store.access.ColumnOrdering in project derby by apache.

the class InsertResultSet method emptyIndexes.

/**
 * Empty the indexes after doing a bulk insert replace
 * where the table has 0 rows after the replace.
 * RESOLVE: This method is ugly!  Prior to 2.0, we simply
 * scanned back across the table to build the indexes.  We
 * changed this in 2.0 to populate the sorters via a call back
 * as we populated the table.  Doing a 0 row replace into a
 * table with indexes is a degenerate case, hence we allow
 * ugly and unoptimized code.
 *
 * @exception StandardException		Thrown on failure
 */
private void emptyIndexes(long newHeapConglom, InsertConstantAction constants, TableDescriptor td, DataDictionary dd, ExecRow fullTemplate) throws StandardException {
    int numIndexes = constants.irgs.length;
    ExecIndexRow[] idxRows = new ExecIndexRow[numIndexes];
    ExecRow baseRows;
    ColumnOrdering[][] order = new ColumnOrdering[numIndexes][];
    int numColumns = td.getNumberOfColumns();
    collation = new int[numIndexes][];
    // Create the BitSet for mapping the partial row to the full row
    FormatableBitSet bitSet = new FormatableBitSet(numColumns + 1);
    // Need to check each index for referenced columns
    int numReferencedColumns = 0;
    for (int index = 0; index < numIndexes; index++) {
        int[] baseColumnPositions = constants.irgs[index].baseColumnPositions();
        for (int bcp = 0; bcp < baseColumnPositions.length; bcp++) {
            if (!bitSet.get(baseColumnPositions[bcp])) {
                bitSet.set(baseColumnPositions[bcp]);
                numReferencedColumns++;
            }
        }
    }
    // We can finally create the partial base row
    baseRows = activation.getExecutionFactory().getValueRow(numReferencedColumns);
    // Fill in each base row with nulls of the correct data type
    int colNumber = 0;
    for (int index = 0; index < numColumns; index++) {
        if (bitSet.get(index + 1)) {
            colNumber++;
            // NOTE: 1-based column numbers
            baseRows.setColumn(colNumber, fullTemplate.getColumn(index + 1).cloneValue(false));
        }
    }
    needToDropSort = new boolean[numIndexes];
    sortIds = new long[numIndexes];
    /* Do the initial set up before scanning the heap.
		 * For each index, build a single index row and a sorter.
		 */
    for (int index = 0; index < numIndexes; index++) {
        // create a single index row template for each index
        idxRows[index] = constants.irgs[index].getIndexRowTemplate();
        // Get an index row based on the base row
        // (This call is only necessary here because we need to pass a
        // template to the sorter.)
        constants.irgs[index].getIndexRow(baseRows, rl, idxRows[index], bitSet);
        /* For non-unique indexes, we order by all columns + the RID.
			 * For unique indexes, we just order by the columns.
			 * We create a unique index observer for unique indexes
			 * so that we can catch duplicate key
			 */
        ConglomerateDescriptor cd;
        // Get the ConglomerateDescriptor for the index
        cd = td.getConglomerateDescriptor(constants.indexCIDS[index]);
        int[] baseColumnPositions = constants.irgs[index].baseColumnPositions();
        boolean[] isAscending = constants.irgs[index].isAscending();
        int numColumnOrderings;
        SortObserver sortObserver;
        final IndexRowGenerator indDes = cd.getIndexDescriptor();
        if (indDes.isUnique() || indDes.isUniqueDeferrable()) {
            numColumnOrderings = indDes.isUnique() ? baseColumnPositions.length : baseColumnPositions.length + 1;
            String indexOrConstraintName = cd.getConglomerateName();
            boolean deferred = false;
            boolean uniqueDeferrable = false;
            UUID uniqueDeferrableConstraintId = null;
            if (cd.isConstraint()) {
                // so, the index is backing up a constraint
                ConstraintDescriptor conDesc = dd.getConstraintDescriptor(td, cd.getUUID());
                indexOrConstraintName = conDesc.getConstraintName();
                deferred = lcc.isEffectivelyDeferred(lcc.getCurrentSQLSessionContext(activation), conDesc.getUUID());
                uniqueDeferrable = conDesc.deferrable();
                uniqueDeferrableConstraintId = conDesc.getUUID();
            }
            sortObserver = new UniqueIndexSortObserver(lcc, uniqueDeferrableConstraintId, // don't clone rows
            false, uniqueDeferrable, deferred, indexOrConstraintName, idxRows[index], true, td.getName());
        } else {
            numColumnOrderings = baseColumnPositions.length + 1;
            sortObserver = new BasicSortObserver(false, false, idxRows[index], true);
        }
        order[index] = new ColumnOrdering[numColumnOrderings];
        for (int ii = 0; ii < isAscending.length; ii++) {
            order[index][ii] = new IndexColumnOrder(ii, isAscending[ii]);
        }
        if (numColumnOrderings > isAscending.length) {
            order[index][isAscending.length] = new IndexColumnOrder(isAscending.length);
        }
        // create the sorters
        sortIds[index] = tc.createSort((Properties) null, idxRows[index].getRowArrayClone(), order[index], sortObserver, // not in order
        false, // est rows
        rowCount, // est row size, -1 means no idea
        -1);
        needToDropSort[index] = true;
    }
    // Populate sorters and get the output of each sorter into a row
    // source.  The sorters have the indexed columns only and the columns
    // are in the correct order.
    rowSources = new RowLocationRetRowSource[numIndexes];
    // Fill in the RowSources
    SortController[] sorter = new SortController[numIndexes];
    for (int index = 0; index < numIndexes; index++) {
        sorter[index] = tc.openSort(sortIds[index]);
        sorter[index].completedInserts();
        rowSources[index] = tc.openSortRowSource(sortIds[index]);
    }
    long[] newIndexCongloms = new long[numIndexes];
    // Populate each index
    for (int index = 0; index < numIndexes; index++) {
        ConglomerateController indexCC;
        Properties properties = new Properties();
        ConglomerateDescriptor cd;
        // Get the ConglomerateDescriptor for the index
        cd = td.getConglomerateDescriptor(constants.indexCIDS[index]);
        // Build the properties list for the new conglomerate
        indexCC = tc.openCompiledConglomerate(false, TransactionController.OPENMODE_FORUPDATE, TransactionController.MODE_TABLE, TransactionController.ISOLATION_SERIALIZABLE, constants.indexSCOCIs[index], indexDCOCIs[index]);
        // Get the properties on the old index
        indexCC.getInternalTablePropertySet(properties);
        /* Create the properties that language supplies when creating the
			 * the index.  (The store doesn't preserve these.)
			 */
        int indexRowLength = idxRows[index].nColumns();
        properties.put("baseConglomerateId", Long.toString(newHeapConglom));
        if (cd.getIndexDescriptor().isUnique()) {
            properties.put("nUniqueColumns", Integer.toString(indexRowLength - 1));
        } else {
            properties.put("nUniqueColumns", Integer.toString(indexRowLength));
        }
        if (cd.getIndexDescriptor().isUniqueWithDuplicateNulls() && !cd.getIndexDescriptor().hasDeferrableChecking()) {
            properties.put("uniqueWithDuplicateNulls", Boolean.toString(true));
        }
        properties.put("rowLocationColumn", Integer.toString(indexRowLength - 1));
        properties.put("nKeyFields", Integer.toString(indexRowLength));
        indexCC.close();
        collation[index] = constants.irgs[index].getColumnCollationIds(td.getColumnDescriptorList());
        // We can finally drain the sorter and rebuild the index
        // Populate the index.
        newIndexCongloms[index] = tc.createAndLoadConglomerate("BTREE", idxRows[index].getRowArray(), // default column sort order
        null, collation[index], properties, TransactionController.IS_DEFAULT, rowSources[index], (long[]) null);
        /* Update the DataDictionary
			 *
			 * Update sys.sysconglomerates with new conglomerate #, if the
			 * conglomerate is shared by duplicate indexes, all the descriptors
			 * for those indexes need to be updated with the new number.
			 */
        dd.updateConglomerateDescriptor(td.getConglomerateDescriptors(constants.indexCIDS[index]), newIndexCongloms[index], tc);
        // Drop the old conglomerate
        tc.dropConglomerate(constants.indexCIDS[index]);
    }
}

Example 3 with ColumnOrdering

use of org.apache.derby.iapi.store.access.ColumnOrdering in project derby by apache.

the class T_CreateConglomRet method t_017.

/**
 * Test BTree.openScan(), BtreeScan.init(), BtreeScan.next(),
 * BtreeScan.fetch() with descending indexes.
 *
 * @exception  StandardException  Standard exception policy.
 * @exception  T_Fail  Throws T_Fail on any test failure.
 */
protected boolean t_017(TransactionController tc) throws StandardException, T_Fail {
    T_SecondaryIndexRow index_row = new T_SecondaryIndexRow();
    // base row template - last column is just to make row long so that
    // multiple pages are spanned.
    DataValueDescriptor[] base_row = TemplateRow.newU8Row(4);
    base_row[3] = new SQLChar();
    String string_1500char = new String();
    for (int i = 0; i < 300; i++) string_1500char += "mikem";
    boolean ret_val = true;
    long value = -1;
    long[] col1 = { 1, 3, 4, 4, 4, 5, 5, 5, 6, 7, 9 };
    long[] col2 = { 1, 1, 2, 4, 6, 2, 4, 6, 1, 1, 1 };
    long[] col3 = { 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21 };
    // set of deleted rows to make scans more interesting
    long[] d_col1 = { 0, 2, 3, 4, 4, 5, 5, 5, 6, 7, 8, 10, 11, 12 };
    long[] d_col2 = { 1, 1, 2, 3, 5, 0, 3, 5, 0, 0, 1, 42, 42, 1 };
    long[] d_col3 = { 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104 };
    REPORT("Starting t_017");
    // create the base table
    long base_conglomid = tc.createConglomerate(// create a heap conglomerate
    "heap", // base table template row
    base_row, // column sort order - not required for heap
    null, // default collation
    null, // default properties
    null, // not temporary
    TransactionController.IS_DEFAULT);
    // Open the base table
    ConglomerateController base_cc = tc.openConglomerate(base_conglomid, false, TransactionController.OPENMODE_FORUPDATE, TransactionController.MODE_RECORD, TransactionController.ISOLATION_SERIALIZABLE);
    // initialize the secondary index row - pointing it at base row
    index_row.init(base_row, base_cc.newRowLocationTemplate(), 5);
    Properties properties = createProperties(// no current properties list
    null, // don't allow duplicates
    false, // 4 columns in index row
    5, // non-unique index
    5, // maintain parent links
    true, // base conglom id
    base_conglomid, // row loc in last column
    4);
    // create the index with all the columns in descending order
    ColumnOrdering[] order = new ColumnOrdering[5];
    // descending
    order[0] = new T_ColumnOrderingImpl(0, false);
    // descending
    order[1] = new T_ColumnOrderingImpl(1, false);
    // descending
    order[2] = new T_ColumnOrderingImpl(2, false);
    // descending
    order[3] = new T_ColumnOrderingImpl(3, false);
    // asccending
    order[4] = new T_ColumnOrderingImpl(4, true);
    long index_conglomid = tc.createConglomerate(// create a btree secondary
    "BTREE", // row template
    index_row.getRow(), // column sort order - default
    order, // default collation
    null, // properties
    properties, // not temporary
    TransactionController.IS_DEFAULT);
    // Open the conglomerate.
    ConglomerateController index_cc = tc.openConglomerate(index_conglomid, false, TransactionController.OPENMODE_FORUPDATE, TransactionController.MODE_RECORD, TransactionController.ISOLATION_SERIALIZABLE);
    // Create a row.
    T_SecondaryIndexRow template = new T_SecondaryIndexRow();
    RowLocation row_loc = base_cc.newRowLocationTemplate();
    template.init(base_row, row_loc, 5);
    // insert them in reverse order just to make sure btree is sorting them
    for (int i = col1.length - 1; i >= 0; i--) {
        ((SQLLongint) (template.getRow()[0])).setValue(col1[i]);
        ((SQLLongint) (template.getRow()[1])).setValue(col2[i]);
        ((SQLLongint) (template.getRow()[2])).setValue(col3[i]);
        base_row[3] = new SQLChar(string_1500char);
        base_cc.insertAndFetchLocation(base_row, row_loc);
        // ")" + template);
        if (index_cc.insert(template.getRow()) != 0)
            throw T_Fail.testFailMsg("insert failed");
    }
    index_cc.checkConsistency();
    ((B2IController) index_cc).debugConglomerate();
    ret_val = t_desc_scan_test_cases(tc, index_conglomid, template);
    // may or may not clean these up.
    for (int i = d_col1.length - 1; i >= 0; i--) {
        ((SQLLongint) (template.getRow()[0])).setValue(d_col1[i]);
        ((SQLLongint) (template.getRow()[1])).setValue(d_col2[i]);
        ((SQLLongint) (template.getRow()[2])).setValue(d_col3[i]);
        base_row[3] = new SQLChar(string_1500char);
        base_cc.insertAndFetchLocation(base_row, row_loc);
        // ")" + template);
        if (index_cc.insert(template.getRow()) != 0)
            throw T_Fail.testFailMsg("insert failed");
        // now delete the row.
        base_cc.delete(row_loc);
        ScanController delete_scan = tc.openScan(index_conglomid, false, TransactionController.OPENMODE_FORUPDATE, TransactionController.MODE_RECORD, TransactionController.ISOLATION_SERIALIZABLE, (FormatableBitSet) null, template.getRow(), ScanController.GE, null, template.getRow(), ScanController.GT);
        if (!delete_scan.next()) {
            throw T_Fail.testFailMsg("delete could not find key");
        } else {
            delete_scan.delete();
            if (delete_scan.next())
                throw T_Fail.testFailMsg("delete found more than one key");
        }
        delete_scan.close();
    }
    ret_val = t_desc_scan_test_cases(tc, index_conglomid, template);
    // Close the conglomerate.
    index_cc.close();
    tc.commit();
    REPORT("Ending t_017");
    return (ret_val);
}

Example 4 with ColumnOrdering

use of org.apache.derby.iapi.store.access.ColumnOrdering in project derby by apache.

the class T_CreateConglomRet method t_019.

/**
 * Test BTree.openScan(), BtreeScan.init(), BtreeScan.next(),
 * BtreeScan.fetch() with alternating ascending and descending coulmn
 * sort order indexes.
 *
 * @exception  StandardException  Standard exception policy.
 * @exception  T_Fail  Throws T_Fail on any test failure.
 */
protected boolean t_019(TransactionController tc) throws StandardException, T_Fail {
    T_SecondaryIndexRow index_row = new T_SecondaryIndexRow();
    // base row template - last column is just to make row long so that
    // multiple pages are spanned.
    DataValueDescriptor[] base_row = TemplateRow.newU8Row(4);
    base_row[3] = new SQLChar();
    String string_1500char = new String();
    for (int i = 0; i < 300; i++) string_1500char += "mikem";
    boolean ret_val = true;
    long value = -1;
    long[] col1 = { 1, 3, 4, 4, 4, 5, 5, 5, 6, 7, 9 };
    long[] col2 = { 1, 1, 2, 4, 6, 2, 4, 6, 1, 1, 1 };
    long[] col3 = { 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21 };
    // set of deleted rows to make scans more interesting
    long[] d_col1 = { 0, 2, 3, 4, 4, 5, 5, 5, 6, 7, 8, 10, 11, 12 };
    long[] d_col2 = { 1, 1, 2, 3, 5, 0, 3, 5, 0, 0, 1, 42, 42, 1 };
    long[] d_col3 = { 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104 };
    REPORT("Starting t_019");
    // create the base table
    long base_conglomid = tc.createConglomerate(// create a heap conglomerate
    "heap", // base table template row
    base_row, // column sort order - not required for heap
    null, // default collation
    null, // default properties
    null, // not temporary
    TransactionController.IS_DEFAULT);
    // Open the base table
    ConglomerateController base_cc = tc.openConglomerate(base_conglomid, false, TransactionController.OPENMODE_FORUPDATE, TransactionController.MODE_RECORD, TransactionController.ISOLATION_SERIALIZABLE);
    // initialize the secondary index row - pointing it at base row
    index_row.init(base_row, base_cc.newRowLocationTemplate(), 5);
    Properties properties = createProperties(// no current properties list
    null, // don't allow duplicates
    false, // 4 columns in index row
    5, // non-unique index
    5, // maintain parent links
    true, // base conglom id
    base_conglomid, // row loc in last column
    4);
    // create the index with all the columns in descending order
    ColumnOrdering[] order = new ColumnOrdering[5];
    // Descending
    order[0] = new T_ColumnOrderingImpl(0, false);
    // Ascending
    order[1] = new T_ColumnOrderingImpl(1, true);
    // Ascending
    order[2] = new T_ColumnOrderingImpl(2, true);
    // descending
    order[3] = new T_ColumnOrderingImpl(3, false);
    // asccending
    order[4] = new T_ColumnOrderingImpl(4, true);
    long index_conglomid = tc.createConglomerate(// create a btree secondary
    "BTREE", // row template
    index_row.getRow(), // column sort order - default
    order, // default collation
    null, // properties
    properties, // not temporary
    TransactionController.IS_DEFAULT);
    // Open the conglomerate.
    ConglomerateController index_cc = tc.openConglomerate(index_conglomid, false, TransactionController.OPENMODE_FORUPDATE, TransactionController.MODE_RECORD, TransactionController.ISOLATION_SERIALIZABLE);
    // Create a row.
    T_SecondaryIndexRow template = new T_SecondaryIndexRow();
    RowLocation row_loc = base_cc.newRowLocationTemplate();
    template.init(base_row, row_loc, 5);
    // insert them in reverse order just to make sure btree is sorting them
    for (int i = col1.length - 1; i >= 0; i--) {
        ((SQLLongint) (template.getRow()[0])).setValue(col1[i]);
        ((SQLLongint) (template.getRow()[1])).setValue(col2[i]);
        ((SQLLongint) (template.getRow()[2])).setValue(col3[i]);
        base_row[3] = new SQLChar(string_1500char);
        base_cc.insertAndFetchLocation(base_row, row_loc);
        // ")" + template);
        if (index_cc.insert(template.getRow()) != 0)
            throw T_Fail.testFailMsg("insert failed");
    }
    index_cc.checkConsistency();
    ((B2IController) index_cc).debugConglomerate();
    ret_val = t_ascdesc1_scan_test_cases(tc, index_conglomid, template);
    // may or may not clean these up.
    for (int i = d_col1.length - 1; i >= 0; i--) {
        ((SQLLongint) (template.getRow()[0])).setValue(d_col1[i]);
        ((SQLLongint) (template.getRow()[1])).setValue(d_col2[i]);
        ((SQLLongint) (template.getRow()[2])).setValue(d_col3[i]);
        base_row[3] = new SQLChar(string_1500char);
        base_cc.insertAndFetchLocation(base_row, row_loc);
        // ")" + template);
        if (index_cc.insert(template.getRow()) != 0)
            throw T_Fail.testFailMsg("insert failed");
        // now delete the row.
        base_cc.delete(row_loc);
        ScanController delete_scan = tc.openScan(index_conglomid, false, TransactionController.OPENMODE_FORUPDATE, TransactionController.MODE_RECORD, TransactionController.ISOLATION_SERIALIZABLE, (FormatableBitSet) null, template.getRow(), ScanController.GE, null, template.getRow(), ScanController.GT);
        if (!delete_scan.next()) {
            throw T_Fail.testFailMsg("delete could not find key");
        } else {
            delete_scan.delete();
            if (delete_scan.next())
                throw T_Fail.testFailMsg("delete found more than one key");
        }
        delete_scan.close();
    }
    ret_val = t_ascdesc1_scan_test_cases(tc, index_conglomid, template);
    // Close the conglomerate.
    index_cc.close();
    tc.commit();
    REPORT("Ending t_019");
    return (ret_val);
}

Example 5 with ColumnOrdering

use of org.apache.derby.iapi.store.access.ColumnOrdering in project derby by apache.

the class CreateIndexConstantAction method executeConstantAction.

// INTERFACE METHODS
/**
 *	This is the guts of the Execution-time logic for
 *  creating an index.
 *
 *  <P>
 *  A index is represented as:
 *  <UL>
 *  <LI> ConglomerateDescriptor.
 *  </UL>
 *  No dependencies are created.
 *
 *  @see ConglomerateDescriptor
 *  @see SchemaDescriptor
 *	@see ConstantAction#executeConstantAction
 *
 * @exception StandardException		Thrown on failure
 */
public void executeConstantAction(Activation activation) throws StandardException {
    TableDescriptor td;
    UUID toid;
    ColumnDescriptor columnDescriptor;
    int[] baseColumnPositions;
    IndexRowGenerator indexRowGenerator = null;
    ExecRow[] baseRows;
    ExecIndexRow[] indexRows;
    ExecRow[] compactBaseRows;
    GroupFetchScanController scan;
    RowLocationRetRowSource rowSource;
    long sortId;
    int maxBaseColumnPosition = -1;
    LanguageConnectionContext lcc = activation.getLanguageConnectionContext();
    DataDictionary dd = lcc.getDataDictionary();
    DependencyManager dm = dd.getDependencyManager();
    TransactionController tc = lcc.getTransactionExecute();
    /*
		** Inform the data dictionary that we are about to write to it.
		** There are several calls to data dictionary "get" methods here
		** that might be done in "read" mode in the data dictionary, but
		** it seemed safer to do this whole operation in "write" mode.
		**
		** We tell the data dictionary we're done writing at the end of
		** the transaction.
		*/
    dd.startWriting(lcc);
    /*
		** If the schema descriptor is null, then
		** we must have just read ourselves in.  
		** So we will get the corresponding schema
		** descriptor from the data dictionary.
		*/
    SchemaDescriptor sd = dd.getSchemaDescriptor(schemaName, tc, true);
    /* Get the table descriptor. */
    /* See if we can get the TableDescriptor 
		 * from the Activation.  (Will be there
		 * for backing indexes.)
		 */
    td = activation.getDDLTableDescriptor();
    if (td == null) {
        /* tableId will be non-null if adding an index to
			 * an existing table (as opposed to creating a
			 * table with a constraint with a backing index).
			 */
        if (tableId != null) {
            td = dd.getTableDescriptor(tableId);
        } else {
            td = dd.getTableDescriptor(tableName, sd, tc);
        }
    }
    if (td == null) {
        throw StandardException.newException(SQLState.LANG_CREATE_INDEX_NO_TABLE, indexName, tableName);
    }
    if (td.getTableType() == TableDescriptor.SYSTEM_TABLE_TYPE) {
        throw StandardException.newException(SQLState.LANG_CREATE_SYSTEM_INDEX_ATTEMPTED, indexName, tableName);
    }
    /* Get a shared table lock on the table. We need to lock table before
		 * invalidate dependents, otherwise, we may interfere with the
		 * compilation/re-compilation of DML/DDL.  See beetle 4325 and $WS/
		 * docs/language/SolutionsToConcurrencyIssues.txt (point f).
		 */
    lockTableForDDL(tc, td.getHeapConglomerateId(), false);
    // depended on this table (including this one)
    if (!forCreateTable) {
        dm.invalidateFor(td, DependencyManager.CREATE_INDEX, lcc);
    }
    // Translate the base column names to column positions
    baseColumnPositions = new int[columnNames.length];
    for (int i = 0; i < columnNames.length; i++) {
        // Look up the column in the data dictionary
        columnDescriptor = td.getColumnDescriptor(columnNames[i]);
        if (columnDescriptor == null) {
            throw StandardException.newException(SQLState.LANG_COLUMN_NOT_FOUND_IN_TABLE, columnNames[i], tableName);
        }
        TypeId typeId = columnDescriptor.getType().getTypeId();
        // Don't allow a column to be created on a non-orderable type
        ClassFactory cf = lcc.getLanguageConnectionFactory().getClassFactory();
        boolean isIndexable = typeId.orderable(cf);
        if (isIndexable && typeId.userType()) {
            String userClass = typeId.getCorrespondingJavaTypeName();
            // run the compare method.
            try {
                if (cf.isApplicationClass(cf.loadApplicationClass(userClass)))
                    isIndexable = false;
            } catch (ClassNotFoundException cnfe) {
                // shouldn't happen as we just check the class is orderable
                isIndexable = false;
            }
        }
        if (!isIndexable) {
            throw StandardException.newException(SQLState.LANG_COLUMN_NOT_ORDERABLE_DURING_EXECUTION, typeId.getSQLTypeName());
        }
        // Remember the position in the base table of each column
        baseColumnPositions[i] = columnDescriptor.getPosition();
        if (maxBaseColumnPosition < baseColumnPositions[i])
            maxBaseColumnPosition = baseColumnPositions[i];
    }
    /* The code below tries to determine if the index that we're about
		 * to create can "share" a conglomerate with an existing index.
		 * If so, we will use a single physical conglomerate--namely, the
		 * one that already exists--to support both indexes. I.e. we will
		 * *not* create a new conglomerate as part of this constant action.
         *
         * Deferrable constraints are backed by indexes that are *not* shared
         * since they use physically non-unique indexes and as such are
         * different from indexes used to represent non-deferrable
         * constraints.
		 */
    // check if we have similar indices already for this table
    ConglomerateDescriptor[] congDescs = td.getConglomerateDescriptors();
    boolean shareExisting = false;
    for (int i = 0; i < congDescs.length; i++) {
        ConglomerateDescriptor cd = congDescs[i];
        if (!cd.isIndex())
            continue;
        if (droppedConglomNum == cd.getConglomerateNumber()) {
            /* We can't share with any conglomerate descriptor
				 * whose conglomerate number matches the dropped
				 * conglomerate number, because that descriptor's
				 * backing conglomerate was dropped, as well.  If
				 * we're going to share, we have to share with a
				 * descriptor whose backing physical conglomerate
				 * is still around.
				 */
            continue;
        }
        IndexRowGenerator irg = cd.getIndexDescriptor();
        int[] bcps = irg.baseColumnPositions();
        boolean[] ia = irg.isAscending();
        int j = 0;
        /* The conditions which allow an index to share an existing
			 * conglomerate are as follows:
			 *
			 * 1. the set of columns (both key and include columns) and their 
			 *  order in the index is the same as that of an existing index AND 
			 *
			 * 2. the ordering attributes are the same AND 
			 *
			 * 3. one of the following is true:
			 *    a) the existing index is unique, OR
			 *    b) the existing index is non-unique with uniqueWhenNotNulls
			 *       set to TRUE and the index being created is non-unique, OR
			 *    c) both the existing index and the one being created are
			 *       non-unique and have uniqueWithDuplicateNulls set to FALSE.
             *
             * 4. hasDeferrableChecking is FALSE.
             */
        boolean possibleShare = (irg.isUnique() || !unique) && (bcps.length == baseColumnPositions.length) && !hasDeferrableChecking;
        // is set to true (backing index for unique constraint)
        if (possibleShare && !irg.isUnique()) {
            /* If the existing index has uniqueWithDuplicateNulls set to
				 * TRUE it can be shared by other non-unique indexes; otherwise
				 * the existing non-unique index has uniqueWithDuplicateNulls
				 * set to FALSE, which means the new non-unique conglomerate
				 * can only share if it has uniqueWithDuplicateNulls set to
				 * FALSE, as well.
				 */
            possibleShare = (irg.isUniqueWithDuplicateNulls() || !uniqueWithDuplicateNulls);
        }
        if (possibleShare && indexType.equals(irg.indexType())) {
            for (; j < bcps.length; j++) {
                if ((bcps[j] != baseColumnPositions[j]) || (ia[j] != isAscending[j]))
                    break;
            }
        }
        if (// share
        j == baseColumnPositions.length) {
            /*
				 * Don't allow users to create a duplicate index. Allow if being done internally
				 * for a constraint
				 */
            if (!isConstraint) {
                activation.addWarning(StandardException.newWarning(SQLState.LANG_INDEX_DUPLICATE, indexName, cd.getConglomerateName()));
                return;
            }
            /* Sharing indexes share the physical conglomerate
				 * underneath, so pull the conglomerate number from
				 * the existing conglomerate descriptor.
				 */
            conglomId = cd.getConglomerateNumber();
            /* We create a new IndexRowGenerator because certain
				 * attributes--esp. uniqueness--may be different between
				 * the index we're creating and the conglomerate that
				 * already exists.  I.e. even though we're sharing a
				 * conglomerate, the new index is not necessarily
				 * identical to the existing conglomerate. We have to
				 * keep track of that info so that if we later drop
				 * the shared physical conglomerate, we can figure out
				 * what this index (the one we're creating now) is
				 * really supposed to look like.
				 */
            indexRowGenerator = new IndexRowGenerator(indexType, unique, uniqueWithDuplicateNulls, // uniqueDeferrable
            false, // deferrable indexes are not shared
            false, baseColumnPositions, isAscending, baseColumnPositions.length);
            // DERBY-655 and DERBY-1343
            // Sharing indexes will have unique logical conglomerate UUIDs.
            conglomerateUUID = dd.getUUIDFactory().createUUID();
            shareExisting = true;
            break;
        }
    }
    /* If we have a droppedConglomNum then the index we're about to
		 * "create" already exists--i.e. it has an index descriptor and
		 * the corresponding information is already in the system catalogs.
		 * The only thing we're missing, then, is the physical conglomerate
		 * to back the index (because the old conglomerate was dropped).
		 */
    boolean alreadyHaveConglomDescriptor = (droppedConglomNum > -1L);
    /* If this index already has an essentially same one, we share the
		 * conglomerate with the old one, and just simply add a descriptor
		 * entry into SYSCONGLOMERATES--unless we already have a descriptor,
		 * in which case we don't even need to do that.
		 */
    DataDescriptorGenerator ddg = dd.getDataDescriptorGenerator();
    if (shareExisting && !alreadyHaveConglomDescriptor) {
        ConglomerateDescriptor cgd = ddg.newConglomerateDescriptor(conglomId, indexName, true, indexRowGenerator, isConstraint, conglomerateUUID, td.getUUID(), sd.getUUID());
        dd.addDescriptor(cgd, sd, DataDictionary.SYSCONGLOMERATES_CATALOG_NUM, false, tc);
        // add newly added conglomerate to the list of conglomerate
        // descriptors in the td.
        ConglomerateDescriptorList cdl = td.getConglomerateDescriptorList();
        cdl.add(cgd);
    // can't just return yet, need to get member "indexTemplateRow"
    // because create constraint may use it
    }
    // Describe the properties of the index to the store using Properties
    // RESOLVE: The following properties assume a BTREE index.
    Properties indexProperties;
    if (properties != null) {
        indexProperties = properties;
    } else {
        indexProperties = new Properties();
    }
    // Tell it the conglomerate id of the base table
    indexProperties.put("baseConglomerateId", Long.toString(td.getHeapConglomerateId()));
    if (uniqueWithDuplicateNulls && !hasDeferrableChecking) {
        if (dd.checkVersion(DataDictionary.DD_VERSION_DERBY_10_4, null)) {
            indexProperties.put("uniqueWithDuplicateNulls", Boolean.toString(true));
        } else {
            // index creating a unique index instead.
            if (uniqueWithDuplicateNulls) {
                unique = true;
            }
        }
    }
    // All indexes are unique because they contain the RowLocation.
    // The number of uniqueness columns must include the RowLocation
    // if the user did not specify a unique index.
    indexProperties.put("nUniqueColumns", Integer.toString(unique ? baseColumnPositions.length : baseColumnPositions.length + 1));
    // By convention, the row location column is the last column
    indexProperties.put("rowLocationColumn", Integer.toString(baseColumnPositions.length));
    // For now, all columns are key fields, including the RowLocation
    indexProperties.put("nKeyFields", Integer.toString(baseColumnPositions.length + 1));
    // For now, assume that all index columns are ordered columns
    if (!shareExisting) {
        if (dd.checkVersion(DataDictionary.DD_VERSION_DERBY_10_4, null)) {
            indexRowGenerator = new IndexRowGenerator(indexType, unique, uniqueWithDuplicateNulls, uniqueDeferrable, (hasDeferrableChecking && constraintType != DataDictionary.FOREIGNKEY_CONSTRAINT), baseColumnPositions, isAscending, baseColumnPositions.length);
        } else {
            indexRowGenerator = new IndexRowGenerator(indexType, unique, false, false, false, baseColumnPositions, isAscending, baseColumnPositions.length);
        }
    }
    /* Now add the rows from the base table to the conglomerate.
		 * We do this by scanning the base table and inserting the
		 * rows into a sorter before inserting from the sorter
		 * into the index.  This gives us better performance
		 * and a more compact index.
		 */
    rowSource = null;
    sortId = 0;
    // set to true once the sorter is created
    boolean needToDropSort = false;
    /* bulkFetchSIze will be 16 (for now) unless
		 * we are creating the table in which case it
		 * will be 1.  Too hard to remove scan when
		 * creating index on new table, so minimize
		 * work where we can.
		 */
    int bulkFetchSize = (forCreateTable) ? 1 : 16;
    int numColumns = td.getNumberOfColumns();
    int approximateRowSize = 0;
    // Create the FormatableBitSet for mapping the partial to full base row
    FormatableBitSet bitSet = new FormatableBitSet(numColumns + 1);
    for (int index = 0; index < baseColumnPositions.length; index++) {
        bitSet.set(baseColumnPositions[index]);
    }
    FormatableBitSet zeroBasedBitSet = RowUtil.shift(bitSet, 1);
    // Start by opening a full scan on the base table.
    scan = tc.openGroupFetchScan(td.getHeapConglomerateId(), // hold
    false, // open base table read only
    0, TransactionController.MODE_TABLE, TransactionController.ISOLATION_SERIALIZABLE, // all fields as objects
    zeroBasedBitSet, // startKeyValue
    (DataValueDescriptor[]) null, // not used when giving null start posn.
    0, // qualifier
    null, // stopKeyValue
    (DataValueDescriptor[]) null, // not used when giving null stop posn.
    0);
    // Create an array to put base row template
    baseRows = new ExecRow[bulkFetchSize];
    indexRows = new ExecIndexRow[bulkFetchSize];
    compactBaseRows = new ExecRow[bulkFetchSize];
    try {
        // Create the array of base row template
        for (int i = 0; i < bulkFetchSize; i++) {
            // create a base row template
            baseRows[i] = activation.getExecutionFactory().getValueRow(maxBaseColumnPosition);
            // create an index row template
            indexRows[i] = indexRowGenerator.getIndexRowTemplate();
            // create a compact base row template
            compactBaseRows[i] = activation.getExecutionFactory().getValueRow(baseColumnPositions.length);
        }
        indexTemplateRow = indexRows[0];
        // Fill the partial row with nulls of the correct type
        ColumnDescriptorList cdl = td.getColumnDescriptorList();
        int cdlSize = cdl.size();
        for (int index = 0, numSet = 0; index < cdlSize; index++) {
            if (!zeroBasedBitSet.get(index)) {
                continue;
            }
            numSet++;
            ColumnDescriptor cd = cdl.elementAt(index);
            DataTypeDescriptor dts = cd.getType();
            for (int i = 0; i < bulkFetchSize; i++) {
                // Put the column in both the compact and sparse base rows
                baseRows[i].setColumn(index + 1, dts.getNull());
                compactBaseRows[i].setColumn(numSet, baseRows[i].getColumn(index + 1));
            }
            // Calculate the approximate row size for the index row
            approximateRowSize += dts.getTypeId().getApproximateLengthInBytes(dts);
        }
        // Get an array of RowLocation template
        RowLocation[] rl = new RowLocation[bulkFetchSize];
        for (int i = 0; i < bulkFetchSize; i++) {
            rl[i] = scan.newRowLocationTemplate();
            // Get an index row based on the base row
            indexRowGenerator.getIndexRow(compactBaseRows[i], rl[i], indexRows[i], bitSet);
        }
        /* now that we got indexTemplateRow, done for sharing index
			 */
        if (shareExisting)
            return;
        /* For non-unique indexes, we order by all columns + the RID.
			 * For unique indexes, we just order by the columns.
			 * We create a unique index observer for unique indexes
			 * so that we can catch duplicate key.
			 * We create a basic sort observer for non-unique indexes
			 * so that we can reuse the wrappers during an external
			 * sort.
			 */
        int numColumnOrderings;
        SortObserver sortObserver;
        Properties sortProperties = null;
        if (unique || uniqueWithDuplicateNulls || uniqueDeferrable) {
            // if the index is a constraint, use constraintname in
            // possible error message
            String indexOrConstraintName = indexName;
            if (conglomerateUUID != null) {
                ConglomerateDescriptor cd = dd.getConglomerateDescriptor(conglomerateUUID);
                if ((isConstraint) && (cd != null && cd.getUUID() != null && td != null)) {
                    ConstraintDescriptor conDesc = dd.getConstraintDescriptor(td, cd.getUUID());
                    indexOrConstraintName = conDesc.getConstraintName();
                }
            }
            if (unique || uniqueDeferrable) {
                numColumnOrderings = unique ? baseColumnPositions.length : baseColumnPositions.length + 1;
                sortObserver = new UniqueIndexSortObserver(lcc, constraintID, true, uniqueDeferrable, initiallyDeferred, indexOrConstraintName, indexTemplateRow, true, td.getName());
            } else {
                // unique with duplicate nulls allowed.
                numColumnOrderings = baseColumnPositions.length + 1;
                // tell transaction controller to use the unique with
                // duplicate nulls sorter, when making createSort() call.
                sortProperties = new Properties();
                sortProperties.put(AccessFactoryGlobals.IMPL_TYPE, AccessFactoryGlobals.SORT_UNIQUEWITHDUPLICATENULLS_EXTERNAL);
                // use sort operator which treats nulls unequal
                sortObserver = new UniqueWithDuplicateNullsIndexSortObserver(lcc, constraintID, true, (hasDeferrableChecking && constraintType != DataDictionary.FOREIGNKEY_CONSTRAINT), initiallyDeferred, indexOrConstraintName, indexTemplateRow, true, td.getName());
            }
        } else {
            numColumnOrderings = baseColumnPositions.length + 1;
            sortObserver = new BasicSortObserver(true, false, indexTemplateRow, true);
        }
        ColumnOrdering[] order = new ColumnOrdering[numColumnOrderings];
        for (int i = 0; i < numColumnOrderings; i++) {
            order[i] = new IndexColumnOrder(i, unique || i < numColumnOrderings - 1 ? isAscending[i] : true);
        }
        // create the sorter
        sortId = tc.createSort(sortProperties, indexTemplateRow.getRowArrayClone(), order, sortObserver, // not in order
        false, scan.getEstimatedRowCount(), // est row size, -1 means no idea
        approximateRowSize);
        needToDropSort = true;
        // Populate sorter and get the output of the sorter into a row
        // source.  The sorter has the indexed columns only and the columns
        // are in the correct order.
        rowSource = loadSorter(baseRows, indexRows, tc, scan, sortId, rl);
        conglomId = tc.createAndLoadConglomerate(indexType, // index row template
        indexTemplateRow.getRowArray(), // colums sort order
        order, indexRowGenerator.getColumnCollationIds(td.getColumnDescriptorList()), indexProperties, // not temporary
        TransactionController.IS_DEFAULT, rowSource, (long[]) null);
    } finally {
        /* close the table scan */
        if (scan != null)
            scan.close();
        /* close the sorter row source before throwing exception */
        if (rowSource != null)
            rowSource.closeRowSource();
        /*
			** drop the sort so that intermediate external sort run can be
			** removed from disk
			*/
        if (needToDropSort)
            tc.dropSort(sortId);
    }
    ConglomerateController indexController = tc.openConglomerate(conglomId, false, 0, TransactionController.MODE_TABLE, TransactionController.ISOLATION_SERIALIZABLE);
    // Check to make sure that the conglomerate can be used as an index
    if (!indexController.isKeyed()) {
        indexController.close();
        throw StandardException.newException(SQLState.LANG_NON_KEYED_INDEX, indexName, indexType);
    }
    indexController.close();
    // 
    if (!alreadyHaveConglomDescriptor) {
        ConglomerateDescriptor cgd = ddg.newConglomerateDescriptor(conglomId, indexName, true, indexRowGenerator, isConstraint, conglomerateUUID, td.getUUID(), sd.getUUID());
        dd.addDescriptor(cgd, sd, DataDictionary.SYSCONGLOMERATES_CATALOG_NUM, false, tc);
        // add newly added conglomerate to the list of conglomerate
        // descriptors in the td.
        ConglomerateDescriptorList cdl = td.getConglomerateDescriptorList();
        cdl.add(cgd);
        /* Since we created a new conglomerate descriptor, load
			 * its UUID into the corresponding field, to ensure that
			 * it is properly set in the StatisticsDescriptor created
			 * below.
			 */
        conglomerateUUID = cgd.getUUID();
    }
    CardinalityCounter cCount = (CardinalityCounter) rowSource;
    long numRows = cCount.getRowCount();
    if (addStatistics(dd, indexRowGenerator, numRows)) {
        long[] c = cCount.getCardinality();
        for (int i = 0; i < c.length; i++) {
            StatisticsDescriptor statDesc = new StatisticsDescriptor(dd, dd.getUUIDFactory().createUUID(), conglomerateUUID, td.getUUID(), "I", new StatisticsImpl(numRows, c[i]), i + 1);
            dd.addDescriptor(statDesc, null, DataDictionary.SYSSTATISTICS_CATALOG_NUM, true, tc);
        }
    }
}