Examples with HashIndex org.h2.index.HashIndex used on opensource projects

Example 1 with HashIndex

use of org.h2.index.HashIndex in project h2database by h2database.

the class RegularTable method addIndex.

@Override
public Index addIndex(Session session, String indexName, int indexId, IndexColumn[] cols, IndexType indexType, boolean create, String indexComment) {
    if (indexType.isPrimaryKey()) {
        for (IndexColumn c : cols) {
            Column column = c.column;
            if (column.isNullable()) {
                throw DbException.get(ErrorCode.COLUMN_MUST_NOT_BE_NULLABLE_1, column.getName());
            }
            column.setPrimaryKey(true);
        }
    }
    boolean isSessionTemporary = isTemporary() && !isGlobalTemporary();
    if (!isSessionTemporary) {
        database.lockMeta(session);
    }
    Index index;
    if (isPersistIndexes() && indexType.isPersistent()) {
        int mainIndexColumn;
        if (database.isStarting() && database.getPageStore().getRootPageId(indexId) != 0) {
            mainIndexColumn = -1;
        } else if (!database.isStarting() && mainIndex.getRowCount(session) != 0) {
            mainIndexColumn = -1;
        } else {
            mainIndexColumn = getMainIndexColumn(indexType, cols);
        }
        if (mainIndexColumn != -1) {
            mainIndex.setMainIndexColumn(mainIndexColumn);
            index = new PageDelegateIndex(this, indexId, indexName, indexType, mainIndex, create, session);
        } else if (indexType.isSpatial()) {
            index = new SpatialTreeIndex(this, indexId, indexName, cols, indexType, true, create, session);
        } else {
            index = new PageBtreeIndex(this, indexId, indexName, cols, indexType, create, session);
        }
    } else {
        if (indexType.isHash()) {
            if (cols.length != 1) {
                throw DbException.getUnsupportedException("hash indexes may index only one column");
            }
            if (indexType.isUnique()) {
                index = new HashIndex(this, indexId, indexName, cols, indexType);
            } else {
                index = new NonUniqueHashIndex(this, indexId, indexName, cols, indexType);
            }
        } else if (indexType.isSpatial()) {
            index = new SpatialTreeIndex(this, indexId, indexName, cols, indexType, false, true, session);
        } else {
            index = new TreeIndex(this, indexId, indexName, cols, indexType);
        }
    }
    if (database.isMultiVersion()) {
        index = new MultiVersionIndex(index, this);
    }
    if (index.needRebuild() && rowCount > 0) {
        try {
            Index scan = getScanIndex(session);
            long remaining = scan.getRowCount(session);
            long total = remaining;
            Cursor cursor = scan.find(session, null, null);
            long i = 0;
            int bufferSize = (int) Math.min(rowCount, database.getMaxMemoryRows());
            ArrayList<Row> buffer = new ArrayList<>(bufferSize);
            String n = getName() + ":" + index.getName();
            int t = MathUtils.convertLongToInt(total);
            while (cursor.next()) {
                database.setProgress(DatabaseEventListener.STATE_CREATE_INDEX, n, MathUtils.convertLongToInt(i++), t);
                Row row = cursor.get();
                buffer.add(row);
                if (buffer.size() >= bufferSize) {
                    addRowsToIndex(session, buffer, index);
                }
                remaining--;
            }
            addRowsToIndex(session, buffer, index);
            if (SysProperties.CHECK && remaining != 0) {
                DbException.throwInternalError("rowcount remaining=" + remaining + " " + getName());
            }
        } catch (DbException e) {
            getSchema().freeUniqueName(indexName);
            try {
                index.remove(session);
            } catch (DbException e2) {
                // this could happen, for example on failure in the storage
                // but if that is not the case it means
                // there is something wrong with the database
                trace.error(e2, "could not remove index");
                throw e2;
            }
            throw e;
        }
    }
    index.setTemporary(isTemporary());
    if (index.getCreateSQL() != null) {
        index.setComment(indexComment);
        if (isSessionTemporary) {
            session.addLocalTempTableIndex(index);
        } else {
            database.addSchemaObject(session, index);
        }
    }
    indexes.add(index);
    setModified();
    return index;
}