[PHOENIX-2110] Primary key changes should be pushed to diverged views

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 4.5.0
• Assignee: Samarth Jain
• Reporter: James R. Taylor
• Created: 12/Jul/15 07:00
• Updated: 21/Nov/15 02:16
• Resolved: 22/Jul/15 18:46

Description

If a view is diverged, we should not abort the adding of a column to the base table. Instead, we should add it if it's a PK (as otherwise the view will become unusable) and not add it otherwise. If that's problematic, then perhaps we can just block it if a PK column is being added.

The code is in MetaDataEndPointImpl here:

    private MetaDataMutationResult addRowsToChildViews(List<Mutation> tableMetadata, List<Mutation> mutationsForAddingColumnsToViews, byte[] schemaName, byte[] tableName,
            List<ImmutableBytesPtr> invalidateList, long clientTimeStamp, TableViewFinderResult childViewsResult,
            Region region, List<RowLock> locks) throws IOException, SQLException {
        for (Result viewResult : childViewsResult.getResults()) {
            byte[][] rowViewKeyMetaData = new byte[3][];
            getVarChars(viewResult.getRow(), 3, rowViewKeyMetaData);
            byte[] viewTenantId = rowViewKeyMetaData[PhoenixDatabaseMetaData.TENANT_ID_INDEX];
            byte[] viewSchemaName = rowViewKeyMetaData[PhoenixDatabaseMetaData.SCHEMA_NAME_INDEX];
            byte[] viewName = rowViewKeyMetaData[PhoenixDatabaseMetaData.TABLE_NAME_INDEX];
            byte[] viewKey = SchemaUtil.getTableKey(viewTenantId, viewSchemaName, viewName);
            // lock the rows corresponding to views so that no other thread can modify the view meta-data
            RowLock viewRowLock = acquireLock(region, viewKey, locks);
            PTable view = doGetTable(viewKey, clientTimeStamp, viewRowLock);
            if (view.getBaseColumnCount() == QueryConstants.DIVERGED_VIEW_BASE_COLUMN_COUNT) {
                // if a view has divorced itself from the base table, we don't allow schema changes
                // to be propagated to it.
            	return new MetaDataMutationResult(MutationCode.UNALLOWED_TABLE_MUTATION, EnvironmentEdgeManager.currentTimeMillis(), null);
            }