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

Example 1 with ScanControllerRowSource

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

the class MergeSort method openSortRowSource.

/**
 *	Open a row source to get rows out of the sorter.
 *	@see Sort#openSortRowSource
 */
public ScanControllerRowSource openSortRowSource(TransactionManager tran) throws StandardException {
    if (SanityManager.DEBUG)
        SanityManager.ASSERT(state == STATE_DONE_INSERTING);
    ScanControllerRowSource rowSource = null;
    if (mergeRuns == null || mergeRuns.size() == 0) {
        // There were no merge runs so we can just return
        // the rows from the sort buffer.
        scan = new SortBufferRowSource(sortBuffer, tran, sortObserver, false, sortBufferMax);
        rowSource = (ScanControllerRowSource) scan;
        // The scan now owns the sort buffer
        sortBuffer = null;
    } else {
        // Dump the rows in the sort buffer to a merge run.
        long containerId = createMergeRun(tran, sortBuffer);
        mergeRuns.addElement(containerId);
        // the number of merge runs
        if (mergeRuns.size() > ExternalSortFactory.DEFAULT_MAX_MERGE_RUN || mergeRuns.size() > sortBuffer.capacity())
            multiStageMerge(tran);
        // There are now few enough merge runs to sort
        // at once, so create a rowSource for them.
        MergeScanRowSource msRowSource = new MergeScanRowSource(this, tran, sortBuffer, mergeRuns, sortObserver, false);
        if (!msRowSource.init(tran)) {
            throw StandardException.newException(SQLState.SORT_COULD_NOT_INIT);
        }
        scan = msRowSource;
        rowSource = msRowSource;
        // The scan now owns the sort buffer and merge runs.
        sortBuffer = null;
        mergeRuns = null;
    }
    // Ready to start retrieving rows.
    this.state = STATE_SCANNING;
    return rowSource;
}

Example 2 with ScanControllerRowSource

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

the class RAMTransaction method openSortRowSource.

/**
 *	@see TransactionController#openSortRowSource
 *	@exception StandardException Standard error policy.
 */
public RowLocationRetRowSource openSortRowSource(long id) throws StandardException {
    Sort sort;
    // if it doesn't exist.
    if (sorts == null || id >= sorts.size() || (sort = (sorts.get((int) id))) == null) {
        throw StandardException.newException(SQLState.AM_NO_SUCH_SORT, id);
    }
    // Open a scan row source on it.
    ScanControllerRowSource sc = sort.openSortRowSource(this);
    // Keep track of it so we can release on close.
    scanControllers.add((ScanManager) sc);
    return sc;
}