[PHOENIX-4855] Continue to write base table column metadata when creating a view in order to support rollback

• Type: Sub-task
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 4.15.0, 5.1.0
• Assignee: Thomas D'Silva
• Reporter: Thomas D'Silva
• Created: 17/Aug/18 23:26
• Updated: 21/Dec/19 00:55
• Resolved: 17/Oct/18 21:38

Description

Currently we filter out the parent table columns while creating a view. If we have to support rollback we still need to write the parent table column metadata.
Instead of this we should filter out the duplicate columns in MetaDataEndpointImpl.combineColumns

// Here we are passed the parent's columns to add to a view, PHOENIX-3534 allows for a splittable
            // System.Catalog thus we only store the columns that are new to the view, not the parents columns,
            // thus here we remove everything that is ORDINAL.POSITION <= baseColumnCount and update the
            // ORDINAL.POSITIONS to be shifted accordingly.
            // TODO PHOENIX-4767 remove the following code that removes the base table column metadata in the next release 
            if (PTableType.VIEW.equals(tableType) && !ViewType.MAPPED.equals(viewType)) {
                boolean isSalted = MetaDataUtil.getSaltBuckets(tableMetadata, GenericKeyValueBuilder.INSTANCE, new ImmutableBytesWritable()) > 0;
                int baseColumnCount = MetaDataUtil.getBaseColumnCount(tableMetadata) - (isSalted ? 1 : 0);
                if (baseColumnCount > 0) {
                    Iterator<Mutation> mutationIterator = tableMetadata.iterator();
                    while (mutationIterator.hasNext()) {
                        Mutation mutation = mutationIterator.next();
                        // if not null and ordinal position < base column count remove this mutation
                        ImmutableBytesWritable ptr = new ImmutableBytesWritable();
                        MetaDataUtil.getMutationValue(mutation, PhoenixDatabaseMetaData.ORDINAL_POSITION_BYTES,
                            GenericKeyValueBuilder.INSTANCE, ptr);
                        if (MetaDataUtil.getMutationValue(mutation, PhoenixDatabaseMetaData.ORDINAL_POSITION_BYTES,
                            GenericKeyValueBuilder.INSTANCE, ptr)) {
                            int ordinalValue = PInteger.INSTANCE.getCodec().decodeInt(ptr, SortOrder.ASC);
                            if (ordinalValue <= baseColumnCount) {
                                mutationIterator.remove();
                            } else {
                                if (mutation instanceof Put) {
                                    byte[] ordinalPositionBytes = new byte[PInteger.INSTANCE.getByteSize()];
                                    int newOrdinalValue = ordinalValue - baseColumnCount;
                                    PInteger.INSTANCE.getCodec()
                                        .encodeInt(newOrdinalValue, ordinalPositionBytes, 0);
                                    byte[] family = Iterables.getOnlyElement(mutation.getFamilyCellMap().keySet());
                                    MetaDataUtil.mutatePutValue((Put) mutation, family, PhoenixDatabaseMetaData.ORDINAL_POSITION_BYTES, ordinalPositionBytes);
                                }
                            }
                        }
                    }
                }
            }

Issue Links

• duplicates: PHOENIX-4767 Remove code in MetadataEndpointImpl.createTable that removes parent table column metadata
• supercedes: PHOENIX-4879 Add tests for salted tables to AlterMultiTenantTableWithViewsIT
• links to: GitHub Pull Request #339