org.apache.drill.exec.record

Interface RecordBatch

All Superinterfaces:

Iterable<VectorWrapper<?>>, VectorAccessible

All Known Subinterfaces:

CloseableRecordBatch

All Known Implementing Classes:

AbstractBinaryRecordBatch, AbstractRecordBatch, AbstractSingleRecordBatch, ExternalSortBatch, ExternalSortBatch, FilterRecordBatch, FlattenRecordBatch, HashAggBatch, HashJoinBatch, IteratorValidatorBatchIterator, LimitRecordBatch, MergeJoinBatch, MergingRecordBatch, NestedLoopJoinBatch, OrderedPartitionRecordBatch, ProducerConsumerBatch, ProjectRecordBatch, RemovingRecordBatch, ScanBatch, SimpleRecordBatch, SortBatch, SpilledRecordbatch, StreamingAggBatch, TopNBatch, TopNBatch.SimpleSV4RecordBatch, TraceRecordBatch, UnionAllRecordBatch, UnorderedReceiverBatch, WindowFrameRecordBatch, WriterRecordBatch

public interface RecordBatch
extends VectorAccessible

A record batch contains a set of field values for a particular range of records.

In the case of a record batch composed of ValueVectors, ideally a batch fits within L2 cache (~256kB per core). The set of value vectors does not change except during a call to next() that returns RecordBatch.IterOutcome.OK_NEW_SCHEMA value.

A key thing to know is that the Iterator provided by a record batch must align with the rank positions of the field IDs provided using getValueVectorId(org.apache.drill.common.expression.SchemaPath).

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	RecordBatch.IterOutcome Describes the outcome of incrementing RecordBatch forward by a call to next().

Field Summary

Fields

Modifier and Type	Field and Description
static int	MAX_BATCH_SIZE max batch size, limited by 2-byte length in SV2: 65536 = 2^16

Method Summary

Methods

Modifier and Type	Method and Description
FragmentContext	getContext() Gets the FragmentContext of the current query fragment.
VectorContainer	getOutgoingContainer()
int	getRecordCount() Gets the number of records that are within this record.
BatchSchema	getSchema() Gets the current schema of this record batch.
VectorWrapper<?>	getValueAccessorById(Class<?> clazz, int... ids)
TypedFieldId	getValueVectorId(SchemaPath path) Gets the value vector type and ID for the given schema path.
WritableBatch	getWritableBatch() Gets a writable version of this batch.
void	kill(boolean sendUpstream) Informs child nodes that this query should be terminated.
RecordBatch.IterOutcome	next() Updates the data in each Field reading interface for the next range of records.

Methods inherited from interface org.apache.drill.exec.record.VectorAccessible

getSelectionVector2, getSelectionVector4

Methods inherited from interface java.lang.Iterable

iterator

Field Detail

MAX_BATCH_SIZE

static final int MAX_BATCH_SIZE

max batch size, limited by 2-byte length in SV2: 65536 = 2^16

See Also:

Constant Field Values

Method Detail

getContext

FragmentContext getContext()

Gets the FragmentContext of the current query fragment. Useful for reporting failure information or other query-level information.

getSchema

BatchSchema getSchema()

Gets the current schema of this record batch.

May be called only when the most recent call to next(), if any, returned #OK_NEW_SCHEMA or #OK.

The schema changes when and only when next() returns #OK_NEW_SCHEMA.

Specified by:

getSchema in interface VectorAccessible

Returns:

schema of the current batch

getRecordCount

int getRecordCount()

Gets the number of records that are within this record.

Specified by:

getRecordCount in interface VectorAccessible

Returns:

number of records

kill

void kill(boolean sendUpstream)

Informs child nodes that this query should be terminated. Child nodes should use the QueryContext to determine what has happened.

getOutgoingContainer

VectorContainer getOutgoingContainer()

getValueVectorId

TypedFieldId getValueVectorId(SchemaPath path)

Gets the value vector type and ID for the given schema path. The TypedFieldId should store a fieldId which is the same as the ordinal position of the field within the Iterator provided this class's implementation of Iterable.

Specified by:

getValueVectorId in interface VectorAccessible

Parameters:

path - The path where the vector should be located.

Returns:

The local field id associated with this vector. If no field matches this path, this will return a null TypedFieldId

getValueAccessorById

VectorWrapper<?> getValueAccessorById(Class<?> clazz,
                                    int... ids)

Specified by:

getValueAccessorById in interface VectorAccessible

next

RecordBatch.IterOutcome next()

Updates the data in each Field reading interface for the next range of records.

Once a RecordBatch's next() has returned RecordBatch.IterOutcome.NONE or RecordBatch.IterOutcome.STOP, the consumer should no longer call next(). Behavior at this point is undefined and likely to throw an exception.

See RecordBatch.IterOutcome for the protocol (possible sequences of return values).

Returns:

An IterOutcome describing the result of the iteration.

getWritableBatch

WritableBatch getWritableBatch()

Gets a writable version of this batch. Takes over ownership of existing buffers.