Examples with MultiGet com.mapr.db.impl.MultiGet used on opensource projects

Example 1 with MultiGet

use of com.mapr.db.impl.MultiGet in project drill by apache.

the class RestrictedJsonRecordReader method next.

@Override
public int next() {
    Stopwatch watch = Stopwatch.createUnstarted();
    watch.start();
    RestrictedMapRDBSubScanSpec rss = ((RestrictedMapRDBSubScanSpec) this.subScanSpec);
    vectorWriter.allocate();
    vectorWriter.reset();
    if (!rss.readyToGetRowKey()) {
        // when we are in the build schema phase
        if (rss.isBuildSchemaPhase()) {
            readToInitSchema();
        }
        return 0;
    }
    Table table = super.formatPlugin.getJsonTableCache().getTable(subScanSpec.getTableName(), subScanSpec.getUserName());
    final MultiGet multiGet = new MultiGet((BaseJsonTable) table, condition, false, projections);
    int recordCount = 0;
    DBDocumentReaderBase reader = null;
    int maxRecordsForThisBatch = this.maxRecordsToRead > 0 ? Math.min(rss.getMaxRowKeysToBeRead(), this.maxRecordsToRead) : this.maxRecordsToRead == -1 ? rss.getMaxRowKeysToBeRead() : 0;
    Stopwatch timer = Stopwatch.createUnstarted();
    while (recordCount < maxRecordsForThisBatch) {
        ByteBuffer[] rowKeyIds = rss.getRowKeyIdsToRead(batchSize);
        if (rowKeyIds == null) {
            break;
        }
        try {
            timer.start();
            final List<Document> docList = multiGet.doGet(rowKeyIds);
            int index = 0;
            long docsToRead = docList.size();
            // If limit pushdown then stop once we have `limit` rows from multiget i.e. maxRecordsForThisBatch
            if (this.maxRecordsToRead != -1) {
                docsToRead = Math.min(docsToRead, maxRecordsForThisBatch);
            }
            while (index < docsToRead) {
                vectorWriter.setPosition(recordCount);
                reader = (DBDocumentReaderBase) docList.get(index).asReader();
                documentWriter.writeDBDocument(vectorWriter, reader);
                recordCount++;
                index++;
            }
            timer.stop();
        } catch (UserException e) {
            throw UserException.unsupportedError(e).addContext(String.format("Table: %s, document id: '%s'", getTable().getPath(), reader == null ? null : IdCodec.asString(reader.getId()))).build(logger);
        } catch (SchemaChangeException e) {
            if (getIgnoreSchemaChange()) {
                logger.warn("{}. Dropping the row from result.", e.getMessage());
                logger.debug("Stack trace:", e);
            } else {
                throw dataReadError(logger, e);
            }
        }
    }
    vectorWriter.setValueCount(recordCount);
    if (maxRecordsToRead > 0) {
        if (maxRecordsToRead - recordCount >= 0) {
            maxRecordsToRead -= recordCount;
        } else {
            maxRecordsToRead = 0;
        }
    }
    logger.debug("Took {} ms to get {} records, getrowkey {}", watch.elapsed(TimeUnit.MILLISECONDS), recordCount, timer.elapsed(TimeUnit.MILLISECONDS));
    return recordCount;
}